something in me that doesn’t think people that hurt children should be forgiven, at least not without being made to atone

Not forgotten, certainly. Not necessarily even liking them. But part of the materialist view of history is recognizing our decisions are - at least in part - a consequence of our conditions.

I don’t know if I’m bitter or vengeful or what. Maybe.

You're a product of your condition, too. And having feelings isn't a sin.