I agree with the other posters--just let her be. you can't make her feel hurt or sad--you only can make her scared at this point. something I've learned as an adult is (and I have to keep reminding myself of this) is that you can't control how anyone else feels or reacts, you can only control your reaction. the mature thing to do is walk away...

there are other fish in the sea. no need to get upset about this one rejecting you. take care.