After the Second-War, nothing was ever stable. Not really. Some days were bad, some days were worse, and Snape was happy to have people moving on; allowing his existence to fade into the grey of the aftermath. Lupin however, can't seem to understand that.
Though Severus Snape would never admit it, Remus Lupin knew they were more alike than Snape thought. A terrible habit, for example, involving a certain mirror, involving certain desires involving things that can never be achieved. A Wee Bit Slashy.
Partial Songfic; Never Wanted To Dance- Mindless Self Indulgence Drabble-Snape recalls Lilly as he returns to her murderer, again and again.