I'm sorry that your friend is being that way
That happened to me in highschool to, my so called best friend just quit talking to me. It hurt me at the time but now I could care less about her cuz I found out what she was really like
Now I'm better off then she is! But, ya I know it hurts and makes ya angry, but once your out of highschool friends like that don't really matter, atleast not to me
I have friends now that are more genuine and true friends to me than anyone of my highschool friends ever were.