If you bumped into someone who regularly picked on you as a child, what would you say to them?
I'd like to pretend I'd be kind, forgiving of past hurts, but that seems unrealistic. While I'm not a particularly vengeful person, I doubt I'd be able to wish someone well if they'd bullied me for years. (Luckily, this has never been an issue.)
I'm not about to give anyone the satisfaction of a confrontation. That's partly because I'm a coward but mostly because I think it empowers the antagonist. It's good to be loved and bad to be hated, to be sure, but even worse to find out that you're neither. I think the worst feeling comes when you learn that someone you care deeply about to either extreme is completely indifferent to you.
So I hope that if I'm ever in a situation where I confront a former enemy, I'll just keep on walking.