Most Helpful Girl
I'm on the other end of a similar situation. If you two are close enough, just be honest with her, but make sure she knows (and that means that YOU know clearly) whether this is something that might change with time ( i. e. You are or aren't willing work on facing the issues over your last relationship in order to be with her one day) or not. And don't be surprised/ hurt if she moves on and/ or doesn't even want to be friends. It's incredibly frustrating to develop feelings for a guy who likes you back but is too fucked up from his past to give what you have a chance.
Most Helpful Guy
Well, you only friend zone people you don't have feelings for. So that's not an option. You can always just treat her as a friend and nothing more. If you don't make a move she'll likely move onto someone else. So essentially, just do nothing. Don't act on your feelings. If those feelings get too strong, then spend less time with her