Is there something wrong with me or is it her?

sorry if this might be a little long. my friend well she's isn't my friend anymore but she came to my school at the start of the year and we got along not many people liked her and she got bullied but i stood up for her and the bullying stopped. we got along like normal until may where she kept continuously saying that i was annoying her. what ever i said seemed to annoy her. i had an argument with my other friend last week and she decided not to be my friend for this reason. i didn't really know how this concerned her but i got over it. she got some other friends to pick on me and today in french she had a go at me when it was her who called me a 'fashion disaster' and some other really horrible names like whore, slag, *****. i don't understand what i did to deserve this but is it me who's in the wrong or is it her? help...