Just very confused

Now that I know he is cheating I feel so out of control. He does what he wants. We live together because neither of us can afford to just leave the equity in the house. But he continues on with his life while I try to be sure he doesn't spend all the money and I pay the bills, and I pay the mortgage. But without dual incomes we would lose the house. He stays out late with her - pretending to work. Of course when I call the office there is no response. I think he runs around more now to try to get me to walk away with nothing. Almost 30 years together and this is what I get. I told him last week that if he would continue to pay the mortgage and taxes that he could get out and go live with HER. He told me he needed to be out of the marriage by January and I told him that I wouldn't sign any divorce papers until the house is sold and the settlement on paper. He makes four times what I make but thinks I deserve zip. Anyway - I wish he would just agree to the mortgage and get out. I think his gal pal is pregnant and that's why his urgency. He heads to his shrink weekly. I just don't know what to do anymore. We are at a dead end until the house sells and in this market that will take longer than I can stand to have him in the same house with me.