He is terrified of absolution.
He has been absolved before, sprinkled with forgiveness like holy water that banishes his sins and washes him clean. Lexi brushes over his faults like they are nothing, like the trail of bodies and ruined lives are meaningless in the light of his own salvation. She doesn't allow him to grieve, doesn't make restitution a mandatory part of the recovery process. Chicago and San Francisco and Denver and Austin and St. Louis become a wash of cities he barely remembers, their only connection a list of names that repeat endlessly inside his head. The Ripper becomes a whispered legend, a monster he cannot quite reconcile with who he is now. Lexi says that everyone has a past and the only thing that matters now is how he chooses to live his future. Everybody makes mistakes she says and in the absence of God he chooses to believe in her. He can't bear the weight of her disappointment.
He spends the next 80 years living. It is the only compensation he can make, the only way he can balance the lives that were never lived for an existence he will bear indefinitely. He never tells Lexi why he is doing it, because Lexi doesn't believe in looking back, but even if he can no longer recall all of their faces, it helps. He goes to college, climbs Mount Everest, marches for civil rights, protests a war. He lives his life as best he can for those he killed, and each time the blood slides down his throat (squirrel, fox, rabbit, the occasional deer—not human, never human) he tells himself maybe one day it will be enough.
This time, he knows that there can be no amends. Lexi said never look back-but this is not the aftermath of Chicago, and this time he cannot allow himself to believe in a god. He remembers, with clarity so sharp it burns, the exact pressure it takes to sever a head from a neck, the way the blood flows fast at first and then slower and slower, the way sweat and tears make everything salty and slightly acidic, the smell of shit when the bodies finally let go, the way the final mouthful gags him and mixes with bile in the back of his throat. He knows exactly how long it takes to reassemble a body, just how to wipe the blood and urine and feces from the skin and leave them perfect but for the jagged lines he can't smooth straight. He keeps track of the numbers in his head, totals the brunettes and the red-heads, the ones who never cried out and those who couldn't stop screaming. He doesn't know any of their names, but he remembers them, and he knows why they died.
They died for his brother, whose total body count in 145 years might actually surpass his own, if Damon ever bothered to remember. They died for a girl whose continued existence makes their own impossible, whose name is the only one that matters now. He judges the lives of those he chooses to take against the lives of those he loves and finds them wanting. He does not apologize anymore, when he puts the bodies back together, because nothing he does is accidental. Each kill is precise, and he accepts the truth of what they are. He pays for the lives of his brother and his lover with the blood of innocents, and he does not place blame on anyone else. Not anymore. He is judge, jury, and executioner, and he requires no pardon.
When he returns to Mystic Falls, he knows what will come. Elena and Damon will divide him in half, "new Stefan" and "old Stefan" as though if he can just stop eating people, become who they saw him as, everything will be fine. As though everything that he has done, as the though the people he killed for his own selfish refusal to lose the two people he loves best in all the world, mean nothing so long as he returns to them the man they think he was. But they don't know the truth of his life, that "old Stefan" and "new Stefan" and "Ripper Stefan" and "brother Stefan" and "boyfriend Stefan" and "best friend Stefan" and "pacifist Stefan" and "murderer Stefan" and "selfish Stefan" and "selfless Stefan" and "compelled Stefan" and "indebted Stefan" and all the other Stefan's they think they know, are, in the end, just Stefan.
And he is terrified of absolution.