To answer your last question first, figure out who was on the HELOC, and consider calling the lender to inquire. Since it already appears to have happened, however, the question is what you can do about it. There is case law indicating that if your ex fails to follow the decree and you are financially injured by that failure, you can haul your ex back into family court for reimbursement of your loss (presuming you can quantify it) -- so if they do seek collection from you, you can probably make your ex "indemnify" you for the loss/collection.
Obviously, it is important to know EXACTLY what the decree says, so it may be necessary for you to consult with a family law (or credit repair) specialist.
Answered on Nov 15th, 2014 at 1:24 PM