From Bankrate via Yahoo Finance:
More than a decade ago, I co-signed an $18,000 loan for my son's fiancee. Her parents had stopped giving her money, so I stepped in to help. It was a major mistake! She later dumped my son and is now married to another man. I'm no longer in contact with her. Read more
[...] Recently, I received a letter from the company saying it had not received last month's payment and that one of us needs to make that payment in order to keep our good credit rating. I am 63 and self-employed. I have no money to spare. The only thing I do have is a top-notch credit rating, which is now threatened. Do I have any legal recourse?
Moral of the story: Cosign on a loan only if you are prepared to make every single payment.