Partition Suit Question?

After being divorced for 2 yrs, my ex husband and I purchased a house together (not the best decision, we had kids and thought it would work to live in the same house until they were older....wrong!) Both of our names are on the mortage, we have lived in the house 12 yrs. I put a $30,000.00 down payment on the house when it was purchased. He has moved out of the house and left me with all the bills. Originally, I contacted a real estate agent to sell the house, she gave me an estimate of profit for $33,000.00. Now the ex husband has been to an attorney and is threatening a partition suit, because he wants me to either sell or buy him out. Since I paid the down payment with my money and we are only going to make about the same amount about back when it is sold, are the courts going to force me to pay him half of the equity. If you substract my $30,000.00 down payment, it will probably only leave $3,000.00. I would gladly give him $1500.00 to get out of my life! His attorney is also stating that I would need to sell all the possession in the house and give him half of the money. Most of what is in the house was paid by credit cards that in my name only. What a mess!!! Help!