I’m really sorry to hear about the difficult situation you are in. Sadly, there an easy answer in these situations. The cosigner is legally responsible for the debt in the event the borrower doesn’t pay. However, if the loan was modified to new terms without your wife’s consent, there might be something that can be done about it. In that situation, I’d suggest finding a local attorney (because contract law and consumer law can vary from state to state) and bring them a copy of the loan agreement as well as anything else you have pertaining to the loan.

Just saying that you are going to do something isn’t enough to create a legal obligation to do so. However, other circumstances when added to that statement could potentially create a legal obligation.

That all said, this is a question best directed to a local attorney familiar with the laws of your state.

It sucks that you are in this situation after trying to help someone go to school, and I wish you the best of luck.

There isn’t any one thing that usually works. However, there are several items that occasionally work.

Especially right now, private lenders are making efforts to accommodate borrowers struggling financially. Calling your lender and asking for help may work. Just be sure you are getting actual help. A deferment or forbearance just delays your problem by a couple months. Try to come up with a plan that works long term… aka one that gives you a meaningful path to eliminating your debt.

Sometimes filing a complaint against a lender or reaching out to the company’s ombudsman will make a difference. For example, if you have navient or sallie mae, this article might help. More generally, this article can also help.

Just remember that the complaint process is more likely to go well for you if you make reasonable requests to your lender and the refuse to accommodate. If you ask for 0% interest, you are not being reasonable. If you ask for an interest rate reduction so that you can start making progress on your loan, it is a more reasonable request. When you file the complaint, be sure to note the help you asked for and what the lender was willing to do.

It will depend on many different factors. Will you still be working in your eligible job for at least the next ten years?

I’d suggest reading up on FFELP loans and consolidation here:
https://studentloansherpa.com/consolidation-ffel-federal-loans-student-loan-forgiveness/
https://studentloansherpa.com/federal-consolidation-guide/