Your plight is a prime example of why it is not wise to purchase a home with someone who is not a spouse. Your "buddy" does not appear to be your "buddy" any more. You now have two problems. One is legal and the other is practical.
As a practical matter, it is not feasible for you to comfortably live in the same house with another man and his wife/family. To contemplate getting married and moving into such a house with a wife is an invitation to even more conflict. In my humble opinion, it won't work! Don't consider moving back into the house.
Now for the legal part: You are the owner of real property with someone else. The realty can't be feasibly partitioned - that is, divided between you. Therefore, I recommend (unless your former "buddy" agrees to buy you out) that you consult a good real estate attorney in the location of the house, and ask that he advise you on the mechanics and cost of a "Sale for Division." In most states, there is a means to go to court and force a sale of real estate that the owners can't divide, and can't agree on a proper disposition.
Answered on Jan 25th, 2012 at 6:44 PM