Buffy the Vampire Slayer, Season 2

Giles:
[about the ghost of James] He's-he's trying to... resolve whatever issues are keeping him in limbo. What exactly those are, I'm not...

Buffy:
He wants forgiveness.

Giles:
Yes. I imagine he does. But when James possesses people, they act out exactly what happened that night. So he's experiencing a form of purgatory instead. I mean, he's doomed to kill his Ms. Newman over and over and over again, and... Forgiveness is impossible.

Buffy:
Good. He doesn't deserve it.

Giles:
To forgive is an act of compassion, Buffy. It's not done because people deserve it, it's done because they need it.

Buffy:
No. James destroyed the one person he loved the most in a moment of blind passion. And that's not something you forgive. No matter why he did what he did. And no matter if he knows now that it was wrong and selfish and stupid, it is just something he's gonna have to live with.

Xander:
He can't live with it, Buff. He's dead.