Not sure if my two cents count here, but why would you even want to get back with someone who treats you like shit? And why would you stay with someone who cheated on you? I'm afraid I don't understand. I know I for one would never get back together with someone who treated me horribly, and I won't. In all honesty, I wouldn't even remain friends with them. If they treated you that badly during a relationship, who's to say they wouldn't do the same in a friendship?

My advice is simple. Move on. You don't need her. If she cheated on you, get rid of her. If she treats you poorly, get rid of her. Don't learn things the hard way, it causes more damage than it does good.

Anyway, just my two cents, take it or leave it. It's your life and you'll end up doing what you want. =) Good luck with whatever you decide though.