Regretablly, the situation that you describe is a common result of divorce.
The court can award a joint obligation to one party to pay, but if that party doesn't pay, then the other party's credit is damaged.
Bankruptcy will not fix your problem, because the mortgage is a secured debt, and it is not dischargable in bankruptcy. To my knowledge, unless the judge could be convinced to set aside the prior judgment and order the house sold (which, I seriously doubt is possible), there is no recourse.
I note that your attorney said you could sue your ex for being continuously late on the mortgage. But, unless he promised to pay the mortgage on time, you would have no cause of action against him. He was awarded the debt -- so, it's his to pay or default on.
About the only thing that I can think of that you could sue for would be "interferece with prospective contractual relations," and for that you would have to show that your ex's failure to pay was intentional or negligent, and that it was with knowledge of your existing or prospective contracts which would be damaged by his actions.
I don't think you can make that case.
I wish there were a solution to this problem -- if there were, I could make a fortune, because so many need a solution. But, there just isn't any that I'm aware of.
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