A/N: I'm reposting this because I found a few grammatical errors, and wanted to correct them.
Disclaimer: All rights go to JKR.
It was during Defence Against the Dark Arts in fifth year when they first learnt about patronuses. Potter, Black, Lupin and Pettigrew, the Marauders, managed to produce corporeal ones. Potter's is a stag, one that charged right at him (almost right through him) before turning to the doe beside it.
His best friend, Lily, had produced a graceful doe. He knew he ought to feel happy for her, but he was heartbroken instead. For wasn't it said that those with matching patronuses are soulmates?
On the contrary, as soon as the stag turns it's attention to the doe, Lily looks at Potter with contempt before "accidentally" dropping her wand and causing the beautiful creature to vanish. He never forgot that part of the class.
He, on the other hand, produced only a wisp of silver smoke, but who could blame him? Severus had barely any happy memories. None at home, with his abusive father and dying mother, in the environment that had forced him to grow up before his time. None of his so-called friends who favoured the Dark Arts above all, or during their meetings where he never fit in. Of course, there were those with Lily, though only a few without Petunia or the Marauders butting in to make him miserable. Lily offers to help him, but he declines. What was the use when he had near to nothing to use as his happy memory?
No memories with Lily upset are good, he reminded himself, especially that one with the mistletoe which left them both embarrassed and blushing though he had enjoyed the kiss. But the fact that he could not perform the charm was one he could not face, and with his stubborn determination, he spent almost all his spare time practising.
Finally, he succeeded. Concentrating hard on a memory of him and Lily during the Christmas holidays, having a snowball fight, rushing into the house to have hot chocolate, laughing and chatting, then the Evans family offering to take him in, knowing how he dreaded returning to his drunk father, a stream of silver mist formed a shape as it ran around the room, a large four-legged creature of a sort. It slowed down as it neared him, and he gasped.
To his shock, the patronus was a deer. A doe, to be exact. Before knowing what it was, he had wanted to boast to Lily that he had been able to produce a patronus, but now he was having second thoughts.
Months passed by before he had the courage to tell her, confess that he loved her and would do anything as long as she didn't reject him. During that short span of time, his mother had passed away, and Lily was the only one left who was there for him.
I'm going to tell Lily, he vowed one day. After the OWLs are over. It's just Lily, she won't laugh at you, he told himself. And it's true. Severus's childhood friend had been nothing but kind to him, no matter whether she approved or disapproved of what he did.
After the Defence OWL, he follows her, meaning to tell her. However, before he could, he was dangling by a leg in the air due to Potter. He was fuming, but unable to do anything while wandless. How dare they use his own spell on him? Lily tried to intervene, but the words calling her a Mudblood burst from his mouth in his fury. She ran away, and he was filled with remorse, even as the Marauders continued bullying him.
That evening, he apologized, told her everything. But this time, she didn't trust him. He hated it. His only true friend abandoned him, and he had no one else left. He wanted it all to end.
Lily found him on the Astronomy Tower during her patrol as prefect, perched on the rail and ready to fall. She called him a coward, telling him that he should be brave and face it. It was the first time she ever called him names. When he didn't react, she then pleaded him to come down, saying she didn't know what came over her earlier. But his heart had been broken again for the third time, and now he was the one who didn't trust her.
He convinced himself that she deserves another chance after all those that she has given him. He tells her that he suspects that Potter is giving her love potion, and urges her to be careful. She scoffs at that, saying that James (James! Not Potter? he thinks.) would do no such thing. But even with this newfound adoration for Potter, she still stayed with him as they looked at the stars. It was just like old times, and the last time he spoke to Lily.
She wasn't careful, and by breakfast the next day, she was as cold as ever towards Severus, ignoring him. He hated her for not listening to him, hated himself for not stopping her. He avoided her for the rest of their time at Hogwarts, as all the while he threw himself into the Dark Arts, eventually joining Voldemort's ranks.
When Voldemort wanted to kill the Potter's, he begged for Lily to be spared because he had the tiniest hope that the potion had worn off. When he heard that Lily sacrificed herself for Potter's child, that hope died.
Years later, when Dumbledore asked him if he had loved Lily after all that time, he replies with always, sending his doe patronus flying through the room.
Dumbledore misunderstood, though. He never loved that Lily who died in Godric's Hollow. He loved the Lily that had been his childhood friend, the brilliant auburn-haired, emerald-eyed witch who loved everyone, and was in turn loved by all.
He kept his eyes on his patronus, blinking back the tears that came to his eyes. Yes, he would always love the vivacious, cheerful girl that lived on in his memory. He ever so slightly reached out a hand to where the doe was before it dissolved into nothing, only a shadow of what there had once been.