Maybe there was some Veritserum left over in his system, or maybe he was just too exhausted to put on a front, but he found himself answering Dumbledore's questions honestly.
"It wasn't that bad, at Hogwarts. Sure they made fun of my casting, or the fact that I was a rat. Sirius and James especially found the fact that I was a virgin at eighteen hilarious. But...I'd tease Sirius about being able to lick his own bollocks, and James' overcompensation by being a stag. It was just what we did."
It was difficult to admit, but he couldn't lie to himself any longer. He could see now that he'd convinced himself things had been worse than they had been. Let Jacob convince him of that. But somehow, it was easier to talk about this, than about love. And he really didn't wnat to know about Dumbledore and Grindlewald. Just...no.
"I don't know when it changed, or when I thought it did. And I don't know why I'm telling you this. It's not as if it matters now. They won't forgive me." He pulled his legs tighter to his chest and now that he'd started he couldn't stop. "After Hogwarts...I thought we'd all get a place together, but James had Lily and Sirius and Remus got their flat. No one thought about me. I had nothing, and no one cared. Jacob cared though, or was convincing enough that I thought he did. He made so much sense, pointing out how Sirius and the others had used me, and then forgotten me when I was no longer useful. Maybe I wanted to believe him, I don't know."
At Dumbledore's last question he shrugged. "I don't think it matters. What's here to live for? It doesn't seem worth it. I thought about ending it, after the Order killed Jacob. But apparently instead I sold out to Voldemort. Real brave of me. I don't think I'll ever know why, but it's damned me and it's not worth it to fight. Everyone turns away anyway."
And he was talking way too much. It was the headache pounding at his temples, the exhaustion sunk deep into his bones. He made himself shut up, as he'd already given Dumbledore far too much power of him by admitting all this. Admitting it to himself too.