Husband cheated during marriage, but didn't find out until after the divorce. Can anything be done?

First and foremost you are her friend so I can understand why you would defend her, but please keep in mind you only heard her part of their marriage..after being married 33 years I can ure you that not just one person is at fault in a marriage. She can do nothing legally as far as I know, and I'm really sorry but she does sound like she is a little bitter and and wants to pay him back.