Everything is muddled, after that night.
Severus exists in a haze, Occlumency and force of will blocking out what he does not want to dwell on, years of practice compartmentalizing his worst experiences making this one just another hurdle to jump through. Though he fought in a war for over three years, he has not yet learned how to grieve, much less for perhaps the two most important people in his life at the same time. He does not want to deal with it. Not now, at least; Dumbledore will undoubtedly require him to visit a Mind Healer once the post-war chaos dies down.
In the immediate aftermath, multiple things happen.
Harry Potter, son of James and Lily, is awarded the title of the Boy-Who-Lived and nationally lauded for apparently surviving the Killing Curse and vanquishing the Dark Lord in the process. Severus is, of course, skeptical, but he can provide no better explanation for why the bodies of his first love and his worst enemy were the only ones in Godric's Hollow that night, aside from the child.
Sirius Black is sentenced to life in Azkaban for the murders of Peter Pettigrew and twelve Muggles, as well as the apparent betrayal of James and Lily Potter to the Dark Lord. He is claimed to have secretly been the Dark Lord's right-hand-man throughout the war, and his mugshot laughs maniacally on the cover of the Daily Prophet, but Severus knows he was never a Death Eater—there is no possible way Black would ever be able to muster the mental fortitude and emotional control required to be a spy.
He is honestly surprised the public is so ready to accept that the hotheaded Gryffindor former heir of the House of Black was, in fact, a servant of the Dark Lord, but he finds he doesn't much care. Perhaps the Dark Lord visited Black personally and tortured him until he cracked and revealed his friends' location, or perhaps he really was just that unstable. Severus hates Black with every bone in his body, and thus does not protest at the somewhat…unclear timeline of events leading up to his arrest.
Four days into November, Bellatrix Lestrange is also sentenced to life in Azkaban, along with her husband Rodolphus, brother-in-law Rabastan, and apprentice (and rumored lover) Barty Crouch, for the crime of rendering renowned Aurors and Order members Frank and Alice Longbottom clinically insane with the Cruciatus Curse. Severus has never particularly liked any of the three Lestranges, but he finds himself somewhat saddened that such a young, promising mind as Barty's will slowly waste away in an Azkaban cell.
There are more trials. Many more. There are, after all, hundreds of prominent Death Eaters to prosecute.
Igor Karkaroff gives many names, including Severus' own as well as those many of his closer colleagues among the Dark Lord's army.
He will never call any of them his friends. There was always an element of bargaining in his relationship with them, from their Slytherin schooldays to their battlefield camaraderie, that eliminated any possibility of true friendship.
Except perhaps Regulus. He was special—but he's been presumed dead since the summer of 1979, and Severus never grieved for him.
As Severus expected him to, Dumbledore vouches for him, waxing poetic about his invaluable contributions to the Order and generally framing him as a victim of the Death Eaters who was led astray and needed to be rescued more than a willing member. He is briefly aggravated by this before realizing that it is necessary for his reputation in the eyes of both the public and his former associates and that Dumbledore embellishing his character in front of the entire country is infinitely better than a life sentence in Azkaban.
Lucius claims he was put under the Imperius curse by the Dark Lord, as do many others—all with noble names and generations of wealth with which to bribe the Wizengamot. It is all a sham, of course—the Dark Mark can only be administered onto a willing servant, the Dark Lord made sure of that—but the general public knows nothing of the inner workings of the Death Eaters, and Severus isn't going to protest his former mentor and a man he respects walking free when perhaps he shouldn't. He'd have no power against the vote of the Wizengamot if he did.
Lucius is suspicious of him at first, which makes sense. No other Death Eater was aware of Severus' position as double agent, just as no member of Dumbledore's Order was—it was deemed too dangerous. But all Severus needs to provide is an explanation of his actions that appeals to Lucius' Slytherin sensibilities and essentially boils down to I was the Dark Lord's spy, not Dumbledore's, and Dumbledore was and is fool enough to trust me, and Lucius is convinced of Severus' continued loyalty to the cause.
As the only other Death Eaters whom he was especially close to in school or afterwards are either dead, missing, or incarcerated, Severus pretty much has all his ducks in a row. Evan Rosier was slain by Alice Longbottom in Diagon Alley in late 1980, Damian Mulciber and Cassius Avery chose Azkaban over betraying their master, and Althea Wilkes fled Britain after she bore her child eighteen months ago. The only outward evidence of Severus' past occupation is the fading Mark on his left forearm, the Mark he was once so proud to wear.
Severus cannot deny that he grew disillusioned by the war, especially during those brutal summer months when Bellatrix brought in the newest batch of freshly-graduated recruits to learn how to cast Unforgiveables and die for a cause their leader didn't believe in.
That, more than most anything, Severus is certain of. A man such as the Dark Lord, a man with such a brilliant mind as his, could not possibly believe in the pseudoscience that is blood purism. Severus never fully believed it, himself, though for a time it was necessary to act as though he did.
That is why his and Lily's friendship never worked out, he muses. She never understood that by walking the tightrope in Slytherin he did, he was saving both his own neck and hers, that every time one of the others joked about hurting her in some way he put a stop to it immediately…
But, he thinks, perhaps that's not important anymore. Lily is gone, and he must find some way to continue his life without her, however impossible that may seem. He takes a seat by the fireplace in his childhood home, a home he has no idea why he came back to. He should burn it, he thinks. It holds nothing but bad memories for him.
A knife sits on the table next to him, the only worthwhile present his father ever gave him. Another thing he doesn't know why he's kept all these years.
"Don't let 'em ever get a leg up on you, Russ," Tobias said when he offered it to his son. "An' if they do, don't be afraid to use this to protect yourself."
He remembers his first Death Eater revel, remembers the intense power he felt, being the one in control as he'd never been before. For the first time in his life, he was the one with the upper hand, he could make others feel as powerless and beaten-down as he'd felt so many times, and he wasn't alone.
He remembers immobilizing a Muggle man up against the wall of his house and cutting him open with Sectumsempra just because he could, and thinking of James Potter's face with every scream the man uttered. He remembers Evan voicing his approval after the man was dead, with a hearty "Nice one, Snape!" He remembers being glad someone was proud of him.
There was no reason for him not to unleash like this—it was encouraged, especially as Bellatrix had led that particular raid. He could finally express himself, unburdened by Hogwarts' rules or the Ministry's laws or the general population's disdain for him, Severus Snape, a greasy, dirt-poor, half-blood Slytherin no one gave a fuck about from a shitty Muggle mill town no one even knew the name of. It had been wonderful—a feeling like nothing he'd felt before or since.
He thinks on it now and is disgusted that he was so desperate for release and that rushing sense of power that he would do anything—did do anything—no matter how immoral it was to experience it.
The Dark Lord freed him from all that has crushed and twisted him in his life, and though he thinks he can never forgive the Dark Lord for killing Lily, he knows he will always be grateful for that simple act of his mentor's.
And now, here he sits in his dilapidated apartment, the Dark Lord's favored servant, Firewhiskey in hand, wallowing in self-loathing and regret. Perhaps going to Azkaban would be better than this. He certainly deserves to be there, right next to Bellatrix and Barty and the others who willingly killed and tortured and participated in the height of criminal depravity in the Dark Lord's name. Insulting Black one last time sounds like a fine idea, as well.
Perhaps he'd even enjoy Azkaban. There he'd at least have company, and an excuse to be nihilistic in peace without a manipulative old wizard hovering over him. At least the Dark Lord respected him, and earned his respect in turn; Dumbledore doesn't even try. Severus exchanged one conniving old master for another, but he's not sure if it was worth it.
Here, in this new Britain ruled by Albus Dumbledore and the heroes of the war, Severus Snape is vilified, no matter that he spied for Dumbledore. The whole country knows him as the defective Death Eater, the one who may have ended up on the right side but who started out on the wrong one.
Thirteen years from now, a man Severus will think to be Alastor Moody will tell him "There are some spots that don't come off, Snape," and he will be right.
Now, Dumbledore expects him to become a teacher in nine months' time, and, though he once wished to apply for the very post Dumbledore wants him to take, Severus dreads it as much as he knows he has no choice in the matter. He made oaths to Dumbledore, oaths he didn't have to make. He could have gone to another Order member with the prophecy, perhaps Frank Longbottom or Dorcas Meadowes—neither of them ever outwardly showed hostility to him—but instead he chose Dumbledore, the one man guaranteed to ask for an oath of fealty in return.
Dumbledore wants him close and under control, he knows. Dumbledore would never let his "reformed" spy out of his sight. The trust between them is as frail as Severus' trust that his former Death Eater comrades wouldn't sell him out given half a chance. As much as Dumbledore preaches about soul-saving and giving second chances, Severus knows it's all a lie. Dumbledore knows exactly who Severus Snape is, and he is disgusted by it.
He could have chosen not to go to anyone else, he thinks. Could have left the Dark Lord's side, could have wandered back to Spinner's End with the guilty knowledge that his silence could lead to the death of Lily Evans, the only person who ever gave a shit about him. Had he done that, though, he knows he'd hate himself even more.
He also knows that he could have chosen not to report to the Dark Lord, and it is this knowledge that causes him the most pain. Because he now realizes that Lily Evans would still be alive were it not for his actions. Had he not taken those fateful words to his master, there would have been no reason for the Dark Lord to attack Godric's Hollow that Halloween night. He made the conscious choice to give the Dark Lord a prophecy that, had he thought about before acting, he would've realized would provoke the Dark Lord to pursue Lily Evans.
The weight of his guilt crushes him then, and he slumps over in sadness. He regrets this most of all, more than anything he did in school or as a Death Eater, because he swore he would protect her. He protected her for years, and the second her life was truly on the line he sacrificed it to gain favor with his master. No matter that he begged the Dark Lord to spare her life. He should never have entertained the possibility of endangering her life in the first place.
Dumbledore's instincts were right, he truly is a terrible person. Perhaps Dumbledore thinks he can truly reform Severus—he's too smart not to realize that his spy isn't half as reformed as he outwardly appears to be.
Death would not be a bother to Severus, not right now, while he's drunk and in mourning and full of self-hatred, realizing that for the foreseeable future his life will be spent following Albus Dumbledore's orders. No, death would not be a bother. Perhaps it'd even be a blessing. His eyes turn to the knife, still on the table.
He's had suicidal thoughts before, of course, no shortage of them. He grew up being told he was nothing, and that message was hammered into him by all but two people he ever spent any amount of time around. But nothing like this.
He always had some hope. In school, it was Lily; the knowledge that she would be stricken with grief stilled the knife every time he thought he was going to attempt. During the war, it was the Dark Lord, a man who had given Severus everything he had never been able to obtain himself, a man he will be eternally grateful towards even as he labors to defeat him a second time.
Because Dumbledore believes the Dark Lord isn't fully dead, and, given that he repeatedly bragged that he had mastered the secrets of immortality, Severus is inclined to believe him. Of course, he has no idea how the Dark Lord became immortal, nor how Dumbledore plans to finally kill him, but judging by the wording of the oath the Headmaster gave him he expects it has something to do with Harry Potter, the child of prophecy.
No. It cannot be Potter. Dumbledore is a fool to place so much faith in the ramblings of a madwoman, Seer or not. Severus does not want to spend the rest of his life working with a wise old fool to destroy a man he respected so much. But he has no choice.
He's never been brave enough to commit suicide. Not even that night in sixth year, nearly five years ago, now, when he stood atop the Astronomy Tower preparing to jump. Seventeen years from now there will be many who will say Severus Snape should have been a Gryffindor, but unlike the man who will pose as Mad-Eye Moody, they will be wrong.
That night, atop the Astronomy Tower, was perhaps the worst night of his life until recently. He'd been at his lowest point then, with the Marauders on his back worse than normal and his Housemates expecting things of him, along with all the talk of what everyone was doing after Hogwarts and the realization that he had very few options. No one wanted an ugly, impoverished, half-blood Slytherin from Cokeworth, least of all a potential Potions Master.
And then his mother died of a disease that could have been cured had Tobias allowed her to go to St. Mungos', and he became so utterly tired of everything, of the weight that came with the knowledge that not a single living person gave a shit whether you lived or died, and so he took his wand and his knife and Disillusioned himself and went up to the highest point one could reach in the castle.
He didn't jump, of course. But he spent a long time thinking about it, and five years later he still cannot pinpoint exactly what brought him down from that ledge.
It is this that his thoughts turn to, in late 1981, as the night turns to morning and his Firewhiskey grows cold. He thinks that at least he had some hope in 1976. Lily was alive, and he was gaining more respect from his peers, and he still had a year and a half left of school…
Now, five years later, he has none of those things, and his life is in the hands of a man he does not trust.
He wishes the Dark Lord had won the war. That Lily had not died, and that Dumbledore's twinkling smile of condescension had been silenced along with anyone stupid enough to go against the Dark Lord.
Under the Dark Lord's rule, he'd have everything he had as a Death Eater, except he'd no longer be a vigilante working for the magical equivalent of a terrorist group. He wouldn't have to hide his Dark Mark nor his status as a wizard from anyone, magical or Muggle, because magicals would rule over Muggles as the Dark Lord believed was their right. No child would ever feel the crippling self-loathing that came with having parents that hated you for what you were, that were hostile to you because of something you were born as, something special, something to be worshipped and appreciated rather than despised.
Tobias beat any idealistic notions out of him as a young boy, but Severus takes a moment to bask in the glory of what might have been, and it makes him feel better before he realizes he will have none of that. The Dark Lord is dead, if not forever, and when he returns Severus will have to spy against him as he did before.
The knife on the table seems to gleam in the firelight, enticing Severus. He picks it up, twirling it around like he used to. He lightly brushes the blade against his arm, feeling a very slight prick of pain, but he's used to pain. He's spent his entire life in pain.
He swipes the knife over his arm again, making a cut this time, but it doesn't hurt like he wants it to. He is extremely familiar with the mental art of shielding oneself from pain—he employed it quite a bit as a Death Eater—but now he drops that part of his Occlumency defense and drives the knife in further, wincing as hot blood drips out of his arm. He turns his arm over and points the blade at the base of his Dark Mark, and as he begins to cut, tracing the mark he once so proudly carried with his knife, he lets his shields drop, releasing thoughts and memories he's buried deep in his mind.
Severus screams in agony as his Mark gushes blood and his memories flood out, letting out years of built-up hatred and hurt and grief, emotions he's never dealt with before. His magic flares, causing the fireplace's flame to soar and assorted bottles and vials to crack and shatter.
It is not only his left arm that sears in pain, but his head as well, as years of sometimes-accidental Occlumency protections come crashing down in a wave for the first time.
Tobias slamming his bottle down on the table, shouting at his wife… So loud, Severus can hear it from his room… he's just trying to read… Eileen crying out in pain… "Wretched witch, thinking you can fool me! You even made our sick little brat a freak like you…"
Black's spiteful, mocking voice… "Hey, Snivellus, where are those little junior Death Eater friends of yours? Can't be bothered to save the little half-blood wretch, can they? You're so pathetic not even the Death Eaters want you…"
"Severus… there's someone I'd like you to meet…" Lucius, looking proud and handsome in his robes, the dark, hooded man behind him is watching the room… He exudes power like no one Severus has ever seen before… Is this the man the other Slytherins have been whispering about? The Dark Lord?
Mulciber's demands he has to follow… "Write my essay for me and I won't go after your little Mudblood whore, Snape. Or maybe I will, anyway. She's just a Mudblood, after all, isn't she?" And he says yes, she is, because he has to…
"Why do you even hang out with them, anyway, Sev? They're disgusting! I wish you'd just find other friends…" She doesn't understand that he can't just drop them, they'll make his life hell if he does, and no one else wants to hang out with him anyway, but she wouldn't understand that, she's a naive, popular little Gryffindor who doesn't really understand what it's like…
"Do you, Severus Snape, swear to obey me, your lord and master, faithfully and without dissent, in my quest to purify our world and vanquish Albus Dumbledore and his Muggle-loving sycophants?" He responds with the expected "yes, my Lord," and it is with loyalty and respect that he vows to follow this man's orders from this point forward… this beautiful, powerful, godlike man… He won't regret it until much later…
Dumbledore's barely-concealed condescension… he hates him, Severus realizes, he just hasn't said it yet… "You disgust me…" And there it is, the confirmation of what he's known for years…
The shame… the embarrassment at being violated in such a private way in front of all these people… and then Lily, there to save him… It infuriates him… "I don't need help from filthy Mudbloods like her!" He regrets it as soon as he says it, but the damage is done…
The combination of the overwhelming pain in his arm, the leftover effects of the Firewhiskey, and the literal mental breakdown Severus is experiencing fucks up his mental state in that moment so much that he begins to laugh at the irony of it all.
Of all the people, all the wonderful, powerful, worthy people that could have survived this war, that could have been handed a second chance on a silver platter, why did it have to be him?
He's never been as self-absorbed as his Slytherin colleagues—any potential belief that he was better or superior was beaten out of him by his father's fists—and he has no problem denying that he's scum, the lowest of the low. Especially after what he's done over the past three years.
Dumbledore is right to be disgusted by him. He knowingly committed the most heinous of crimes, knowingly crafted spells and potions to aid in the committing of such crimes, and didn't feel a shred of regret as he did it. That he attempted to atone by spying for the Order means nothing. He and Dumbledore both know that he only did it in a desperate attempt to save Lily's life.
He is a spineless, immoral, cowardly traitor who was never going to amount to anything, and he deserves far, far worse than he got. Perhaps that is Dumbledore's aim, to convince Severus of his own failures and shortcomings as if he is not already entirely aware of them. To convince Severus that he has no worth except as a tool to use against the Dark Lord.
If that is, in fact, Dumbledore's aim, then the wise old fool has already won.
It is with this mindset that Severus laughs harder than he ever has in his life, laughing at the absurdity of the fact that it is he who is still here when so many others are not. Fate truly is a cruel mistress.
As his laughter begins to fade he becomes conscious of the sharp pain in both his head and his left forearm, and he makes a decision.
He fishes his wand out from the inside pocket of his robes, twirling the sleek blackthorn wood between his fingers as he points the tip at his heart. He clears his mind somehow, preparing to utter those infamously powerful two words that murdered the two most important people in his life in an instant.
He's never had trouble casting the Killing Curse before. Accessing the soul-consuming hatred required to properly cast the curse has never been an issue for him. There is no shortage of people for whom he feels enough hatred to fuel this particular curse.
So he encounters no resistance as he speaks the words that he's spoken so many times before, thinking of all the people he's hated in the past. His father, his mother, Potter, Black, Slughorn, McGonagall, Dumbledore, Mulciber, Bellatrix, even the Dark Lord… But most of all himself.
The familiar green light appears at the tip of his jet-black wand, and he holds it in place, not releasing it. Considering.
He desperately wants to die. No matter Dumbledore's hogwash about Lily's son and the prophecy and the Dark Lord's return. Severus no longer cares about any of that. He is beyond caring.
His life has no purpose, no authentic purpose, anyway. Narcissa might shred a few crocodile tears, but she will move on quickly. Dumbledore might mourn the loss of his Death Eater spy, but he will find another replacement Potions teacher, and there are other Death Eaters that can be bribed. Severus isn't even technically a Potions Master, no matter his skill.
He feels much like he felt in 1976, five years ago, hopeless and alone, with no visible way out. Only this time he is truly without options. There is nothing left for him in life except regret and bitterness, and he knows he will be unable to escape it. He will let the past consume him until he is nothing more than Albus Dumbledore's sour old tool, nothing more than something for others to manipulate for their own enjoyment.
But, on this night in November of 1981, as he sits in his chair hating himself more than he possibly ever has, thinking that this might be the time he will finally summon enough bravery to end his own life, he can't.
The green light will not release. Whether it is a side effect of Dumbledore's oaths or just his primal sense of self-preservation keeping him alive, he does not know, but he is unable to finish the job.
He lets out a burst of laughter, clutching his wand to his chest as the green light fades away. His eyes catch on the full moon, bright outside his window, and he himself begins to fade, slipping away into unconsciousness as blood and Firewhiskey drip down his arm onto the stained carpet.