"I'm going to take her and drive to see my family over Christmas, I guess..."
Is there any chance whatsoever that you can go back home for Christmas and STAY there? Just file for divorce and walk away from it all? Get a new job, forget the mortgage and any other joint expenses, get an apartment and ask your family to lend support in any way they can and just LEAVE?
I realize you've been putting money into that house for years, and that it would suck to lose it. But you can force a sale (or him to buy you out) in the course of the divorce, right? This is obviously a question for a lawyer.
If it's cc debt, I'm sure that will also get divided up in the course of a divorce.
But at least you'd be responsible for just a set portion of it, and you wouldn't be living with this guy.