i am really starting to hate my best friend..?

[Katie]

You say you don't have the choice to stop being friends with her, but it would be really bad if you stayed friends with her. This sounds like a REALLY bad friendship. Does she know how you feel about all this?
If she doesn't, try telling her. Maybe she doesn't realize she's doing stuff like that. Hopefully. If that isn't the case, you have to treat this like you would treat a bad bf/gf relationship, and break up with her even though it'll be hard.
Tell her that you can't be friends with her, and stick to your guns. Block her number in your phone, ignore her at school, block her on facebook, twitter, wherever you have contact with her.
That's not a good friendship. It sounds like she has issues, and she may need a friend, but she doesn't need to hurt her friends like that.