Ah ha, you came to the right person. OMG what your friend did was very rude!! That must have been sooo embarassing. I have sort of a similar story, but not really. Well there is this teacher in the school that almost everyone thinks is hot and he is like my friend and I don't think he is hot so then my friend got mad because he payed so much attention to me but not her so she told him I liked him and that was a teacher...excuse me a MARRIED TEACHER!! It was sooo embarassing and it was more embarassing than when we got caught for calling the teachers and one of them knew the whole time but was waiting for us to confess. Anyway, uh, maybe you should tell your friend that it was a rude and annoying thing to do to her and tell her what you thought about it and if she questions you further more just say "mind your business". I am really not much help I am not a person to stick up for myself either except when I am not face-to-face with the person like online. Good luck!