Should I feel guilty?

For one, you need to make better choices in who your friends are. I don't blame you for wanting to burst, I think anyone who's gone through that and hasn't yet would have done so. I mean, for all the times she's kicked you, hit you, and called you names you shouldn't feel guilty at all. The fact that you do just shows what kind of person you are (I mean that in a good way). But seriously, you don't need to be around that person.