She is a flake - drop her before she pulls you further into her needless drama as well.

High School is a tough place, but i figure that since this is the case, you just have to be on your guard. There are probably a lot of students who relate exactly to how you're feeling, it's just striking up a meeting with those people. A lot of this sort of thing happens randomly but sometimes you have to extend yourself. I would just focus on doing what you love and consider friendships a bonus - high school is transitory, if you don't make good friends there you'll have your whole working life ahead of you to try again. I'm not sure how helpful it is right now having friendships that are too involved anyway - it can cause a whole load of other stress and when you have exams, college applications etc to worry about i sometimes think it's more trouble than it's worth. But this is just me.