It looks like you've already done a hell of a lot for this friend. If your boyfriend is best friends with hers, then surely you could have a chat with him to talk to her boyfriend to tel him to go easy on her, and let her make her own mind up. In the end she needs to make a decision that 's going to allow her to do what she wants to do and if that means not listening to her boyfriend you have to make this clear to her.
Just continue to be there for her like you are atm and ressure her that asking for help won't make her look any less capable.