Based on the information stated in your question, it appears you do NOT have any rights to protect your credit. Apparently your ex got the house in the divorce, but the lender is always free to ignore what the divorce court ordered, and the lender can pursue collection against any of the orginial parties who signed on the loan. In the course of your divorce, there should have been some resolution of the mortgage. Typically a divorce court would order that the house be sold or refinanced within a certain period. If there was no such ruling, its up to you to negotiate with your ex, to persuade him to sell or refinance. If protecting your credit is a high priority, you may want to offer a financial incentive to your ex (ie, payment of money).
If your name is on the mortgage, you are just as obligated as he is to make payment on the note. You should contact the mortgage holder directly and see if there is anything you can do to protect yourself.
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