Why is she doing this?

Okay . . . well I have this friend and she still is driving me nuts. she makes me want to pull my hair out. shes my very best friend but my other friend turned her against me. its such a loong story but I just want it to stop.I just want my old frined back. right now shes mad at me for somthing I didnt do but I don’t no how to tell her cause she only listenses to that othre friend. plus, that other friend is a cronick liar. I’ve been thinking about changing schools and somtimes sucide. itll end it all and I can fiannaly be happy. but, everyone says shes not a real frin but I no she is . what do I do ? please help me . I’ve been crying wayyy to longg .