Pulchra Decursus, in Amara Reditum
John doesn't know what he expected to be on the other side of the door. He just got up from his chair and opened it, because that's what you do when someone knocks. You get up from the table where you've been drinking tea and grading papers before heading to work and, because nothing interesting or dangerous happens to John anymore, you open the door without checking who it is first.
It's not a total surprise, though. In the split second before he turns the knob, a faint scent or premonition or hint that only his subconscious knows about tips him off. For a brief moment, his body considers recoiling from the door as though he'd been shocked, but there is no time for the instinct to follow through. He gives the door a small tug and steps back to allow it to swing open, showing its contents like a perverse game show.
Sherlock has a few strands of gray in his hair. Sherlock's hair is close-cropped much like John's. Sherlock's face has more lines and Sherlock's skin has more freckles and Sherlock's cheek has a scar because Sherlock is standing right on the other side of the doorframe, and it occurs to John that the only reason this doesn't completely break him is that his mind is already completely broken, has already exhausted its defense mechanisms. He could pass out, but much like a skydiver with a faulty parachute, John knows that even giving up and shutting down still involves falling and hitting the ground.
John's body shudders once, as Sherlock inhales to prepare for words that he reconsiders and hastily abandons. John clenches his teeth so hard his ears ring and his eyes water as he shakes, because the presence of the man on the other side of the door is so dissonant, is so ridiculously out of sync with the rest of the doctor's reality. If this were a neat little story meant for a stage or a chapter in a book or a television show, he'd lunge forward and hug Sherlock in a moment, or perhaps step back, bring his hand to his mouth, and begin to cry.
Instead, this is John's life and he barely makes it to the kitchen sink before he gets sick.
Sherlock has followed him in, probably out of concern. As John rinses his mouth and the sink out, the older man's posture shifts to broadcast a message of don't you dare fucking touch me and he reels back.
John realizes that he's going to have to say something when he finally turns around, so he takes his time facing the counter. He gets out a glass and a few paracetamol, washes his mouth out again, fills the glass, takes the pills, and drinks the rest of the water at a leisurely pace before turning around again.
When he does, Sherlock's raw voice simply says "John," and the closeness of him is just too much. John finds himself on the couch with his head in his hands and only the broken plate on the floor and the once-neat stack of papers still drifting through the air to remind him how he'd gotten there. The mere presence of that man had caused John to rely on every fixed object in his path for support and John is angry about it.
Sherlock is dead. Sherlock LEFT HIM. The Great Consulting Detectivewho claimed he never gave a shit about what people thought had given up under the pressure of Richard Brook and walked out the door and off a building. Richard Brook— really, Moriarty— hadn't even been alive at that point! They knew the crazy bastard had offed himself first because they'd found a spot where Sherlock had accidentally stepped in the man's blood. So when he jumped, it couldn't have been because Moriarty was forcing him to. But with Moriarty dead, he could no longer prove he was a genius, and living in a world where people didn't believe he was smarter than everyone else was just too much for the detective. Just having John believe in him hadn't been enough.
John hadn't wanted to believe it, but as the detective was fond of saying in the most condescending and degrading manner possible, "when you have eliminated the impossible, whatever remains, however improbable, must be the truth." And it was the highly improbable truth that Sherlock Holmes had not cared enough about John Hamish Watson to live for him.
For a moment, John is carried back to the morgue, where someone convinced him not to look at the body. Molly walked out of the autopsy looking like she'd tried to scrub her skin off, and he wasn't able to blame her. That she'd even been allowed to do the autopsy was obviously Mycroft's doing, and time in Afghanistan had taught John that there was no dirtier feeling than being covered in the blood of someone you cared about but couldn't save. He'd tried to tell her she didn't have to, that he knew it would be hard, but it had all been a rush and she'd just squeaked something back about knowing that he didn't like— hadn't liked— to be touched and he wouldn't have wanted a stranger to do it. The hollow look in her eyes as she stared at John's knees and told him that, "he died immediately. His neck broke the moment he hit the pavement. Not much pain at all," hit him like a blow. Until that point, he'd been on autopilot, soldier mode. Nothing had actually been happening to him, just to a person named John he had the ability to control. Most importantly, Sherlock Holmes wasn't actually dead because he was too smart to die, and this was London, where people he cared about didn't die, were in fact very good at almost but not actually dying. John just had to get though this mess until things calmed down and he could figure out what was really happening.
But as Molly, one of the few people he would trust with his life, came out into the hall and said those words, his defensive disconnect faltered. He slammed himself back against the wall and slid down until he was on the floor, tears blinding him because Sherlock Holmes was dead and it was entirely John's fault. Molly joined him on the floor, but didn't touch him because she was just as disgusted by his failure as he was.
He should have figured out what was going on sooner. He ought to have known that Sherlock would never so thoughtlessly ignore Mrs. Hudson if he thought her in any actual danger. He should have stayed with him, or gotten there faster, or said something different while they were on the phone, or something because now Sherlock was dead and not coming back.
It wasn't until a month later, after the funeral and everything that John began to see that there wasn't anything he could have done differently. It was Sherlock that had made the choice to jump, after all. Sherlock had decided for whatever twisted reason that he needed to be on that roof alone, and it was unlikely that John would ever have been able to change his mind about it. This was Sherlock's doing, and it was only the faint recognition that Sherlock had probably thought he'd had a good reason for it all that kept John from hating him.
One week after that revelation, John swore off alcohol. He refused to let himself fall to a condition he was clearly genetically predisposed to. Harry applauded him for it, causing John to contemplate the irony of a person who supported responsibility and good choices in everyone but herself.
One month later, he was able to sleep through the night, and had begun working at the practice again as a result. Sarah was the perfect co-worker and friend, careful not to pity him or expect anything less than his best.
Two more months passed and John moved back to Baker Street and got a dog. He loved Gladstone, an amicably lazy English bulldog that had made fast friends with Mrs. Hudson. The landlady insisted she had no clue why the dog liked her so much, but John had a feeling it had something to do with Gladstone's developing weight problem and newly-found penchant for begging.
And life had gone on. Sherlock's deductive skills may have been called into question, but John's medical and writing skills never had, and all the press (positive or otherwise) meant that within six months he'd left the practice to begin teaching a new class at King's college on medical writing. He was even doing some work for the BBC as a medical correspondent, and began a serious relationship with one of the other journalists. The aching loss of Sherlock had settled into an ignorable, resentment-tinged throb and life had gone on.
But now, sitting on the couch, John feels the reality of the past three years disintegrate, and his mind stutters as he looks at each event with new perspective.
Mycroft must have known. He must have been the one to pull the strings so that Molly— Molly. Molly KNEW. She must have done. Her actions shift meaning: arms scrubbed raw against the blood of a dead man are now scrubbed in an overzealous attempt to make the faked autopsy convincing. She'd sat apart from him because she hadn't felt a need for the comfort he'd craved. How could she live with herself? How could someone as sweet and caring as Molly needlessly cause so much pain?
John watches the story fall into place in front of him. Molly would never have done something so terrible if there wasn't a need. Not only that, but she would have tried to minimize the amount of sadness by telling him the truth as soon as possible. So it wasn't Sherlock dying that was important; it was what he could accomplish whilst the world thought him dead.
Hope starts swelling in John's stomach, but he can't explain exactly why or what for. After what must have been an age, he looks up at Sherlock, who has tears in his eyes— Jesus Christ— and simply asks, "Why?"
Sherlock lets out a breath in what might be half of a sob. "Moriarty's men were going to kill you, John. He had men. If I hadn't died— if they hadn't thought I'd died— a sniper would have shot you."
All the air is knocked out of John's lungs as the last vestiges of the reality John had lived in since that day at St. Bart's exploded. Sherlock Holmes had not cared enough about John Hamish Watson to live for him, because Sherlock Holmes had cared enough about John Hamish Watson to die for him.