My ex-husband and I have a mortage in both our names. I live in the house and make the payments, he wants to file bankruptcy

You have a valid divorce and yet you are both obligated on the mortgage? That doesn't sound like a final disposition in a divorce case. There has to be more to the story. Divorce means final disposition of the property and usually one party pays off the other or the property is sold and the funds or debt is equitably divided. So, re-read the divorce decree, that's step one.

If his name is on the deed, then in a bankruptcy the house is an asset to him, and if there is any non exempt equity, the funds would be available to pay his creditors.

You've got issues and you should seek a family law attorney with bankruptcy knowledge.

This answer is provided for informational purposes only. True legal advice can only be provided in an office consultation by an attorney licensed in your jurisdiction and with experience in the area of law in which your concern lies.