Oh, I totally agree about the weak sense of self, and her identity being based around the Joker!

Well, I do plan for her to latch onto others at school and devote herself to them! The thing that's tricky is that I really want to keep her recognizable as canon Harley, and if she was going to latch on to a different sort of character than Mister J, that could mess her up. Sooooo... As I have it right now, she has a Joker-ish figure in her history, but still has that really low sense of self-worth at school that leads her to dedicate herself around others, but her main loyalty is still to the person back home so she isn't shaping herself around others if that makes any sense.