Ugh. Just get out. I'm not going to pass judgment on her behaviour, but it's not doing you any good at all. So long as you're seeing her, it's going to stop you getting over her. She doesn't get to determine whether you stay friends, so you need to act on what the best thing for you is, rather than what she'd prefer, even if that hurts her. At the very least, take a break from her for a few months until you've got a better hold of yourself and then resume the friendship on a more honest footing. It sounds like at the moment it's just unhealthy.