Good evening, The trouble is that, from the French creditor's point of view (and French law) you will still be responsible for the mortgage on the house in France and any other debt contracted along with your ex while married.
Obtaining that your ex-husband pay for the credit as stated in the decree will be considered YOUR problem. Namely you will have to sue your ex in order to have him comply with the divorce decree... In the meantime, this will be no concern of the French creditors, and you will remain a co-debtor no matter what (and the easiest one to go after if you live in France and your ex lives in the USA...) Sorry to be the bearer of bad news.
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