ZB,
I'm one that stayed in my M until D graduated from HS. I would not do it again if given the opportunity and my XH was "not" violent. It sounds to me like your children would be better off if you took them with you when you left. I'd definitely see a lawyer and get some advice about custody, etc. How old are your kids. If they're old enough they can choose which parent they want to live with. Good luck to you.