Hi, I am sorry this is happening. You can try talking with her to see if she is willing to stop and get behind the reasons of why she is doing this. I would not take this personal and may have nothing to do with her feeling for you, but rather issues she is having within herself. She would need to want to change and stop his behavior and allow you to be able to support her through this. Her wanting to change is the first step even though you can try talking to her in order to be there for her and be able to help by knowing what is going within her. I wish you well with this and please let me know if I can be of further help.
What i already knew