Anything causing stress in life is bad. Is it the way they talk to you? The way they make you feel? What is causing that stress really?
Did you give up on having a nice relationship with them? Do you want to have a nice relationship with them? Do they want the same thing?
I'd like to know for myself, how important it is to feel good about my relationship with my inlaws. To me it's very important. If things don't go that easy, if the relationship is causing stress, I'd want to resolve it.
Stress is bad. For anyone. To me it's even more important to eliminate any kind of stress. After trying to resolve things, I normally feel much more relaxed, meaning the relationship works much better, or stepping back, having less contact and accepting another less satisfying relationship with my inlaws.
Improvement of relationships with any kind of person, depends on the effort of both sides. Hope I helped you out a little bit:-)