Every situation is different. I don't believe anything with in-laws is normal. I think that if they are friends with the ex that's fine but they should be considerate and respectful of you, your feelings and the fact that you are currently the one doing the work in the family relationship. If they obviously treat the ex more like family than they treat you, then there could be a problem. If they ignore you, rub it in your face all the time about how wonderful the ex is, and treat you like you are insignificant, then that's rude and inconsiderate and they are not respecting you or your relationship with their family member. It is their behavior that creates problems between you and the ex, and then they will criticize you if you don't appreciate being snubbed in favor of an ex. There are some people who are so mean and rude to do this. I know. If the in-laws were considerate and treated you appropriately like family, and the ex appropriately as a friend, then there wouldn't be a problem that I could see. But when they treat the ex like family, and treat you like dirt, there is definitely a big problem.