It's certainly understandable that you do not want to foot the bill for your old spouse's new shoes, but unfortunately the credit card companies don't see it that way -- they just want their money.

Probably your best option would be to pay another visit to the judge who entered the final divorce decree. Go back to court and ask the judge to order your ex to deliver copies of the various statements to you immediately. This is the only definitive way for you to know what charges were actually incurred during the marriage, making you responsible for paying them. You may also want to ask the judge to clarify that you're not responsible for any charges made after your marriage was over.