OMG Tyedye, have just come across this thread. I feel for you and reiterate what most have said here.
No-one should have to tolerate what your P (can't call him DP sorry), is putting you through. You have children, you wouldn't ever want them to think that its ok for people to be treated like that, least of all their mother.
No-one, I repeat, no-one has the 'right' to have sex with another person unless they consent it, married or not. No-one would want to get naked and intimate with a man who is a cruel bully.
You CAN get out, or better still, get HIM out, its your family home, he can find somewhere else to live. You have the support of the MN lot here, there's a lot of good advice on this thread,please, do something soon. Get in touch with mumblechum, as she'd be the one to get the legalities right.
Keep posting, let us know how you're doing.
Much love, stay strong XX