Need Advice on the Joint Owner Situation

[snaka]

What is the name of your state (only U.S. law)? Calilfornia.

Here is the history:

My ex-girlfriend and I bought a condo together while we were dating. After the break-up (8 month later), she chose to vacate the house and left me with the mortgage payment. During the escrow, I have put down about 15k for the down payment but my ex did not contribute. Her grandmother was our real estate agent. When the escrow closed, she gave us all of the commission she received to both of us, which was about 11K. During the break, we finally resolved our issue regarding the 11k and split the money. While she was with me, we paid right down to the middle of bills and mortgages. When she left, she refused to pay her half of the mortgage and left me by myself looking for roommates. I kept making the payment up and til now ( almost 2yrs from break up), but my ex and I didn't have the money we have been putting off making a property taxes.

Current Situation:

Since our property tax is connected to the melo roose, we recently paid what the minimum they require so we don't foreclose our house ($800). Again recently the unpaid property tax caught up with us. I advised the ex to pay her half, and she refuse to pay because she doesn't have the money. I have just enough to cover the past due (8K) but we have 2008-2009 tax due again in Dec (3.5K). Now my ex wants to sign a quick deed over to me, but I know i cannot pay the property tax all by myself not to mention the mortgage and the bills at the same time. I decline her regarding the quick deed and told her that only way she gets her name off is to sell the house. She refused to sell the house. Her grandmother advise me to keep putting the property tax off so the mortgage company can help us pay for the property tax and get monthly payment plan instead of paying it off.

Also not to mention my mortgage rate will reset in 2010 and i know i will not be able to afford once it resets. I have only paid the minimum mortgage payment up until now.

My question:

-What is the best legal situation I can go from here? I know I'll take a loss but I feel taking a current loss is better than take a chance and get a bigger loss later.
-Is there a way where i can take a less loss then my ex because of the all of the payments I have made without her and also the down payment I put down for the
Condo?
-Any other legal advices other than telling me I shouldn't have bought a house together?