When I first got married, my wife and I used to ask really elderly couples for relationship advice. Got some interesting ones. An old cop advised to move far away from old friends and family and start a new life. Where there are no exes or meddling mother-in-laws. That half his cop calls were over asshole family members with no boundaries. Another interesting one was an old Korean vet. His wife said, don't bad-mouth your spouse, because you may get over it, but words can't be unsaid. When they were young he had cheated during a deployment. She forgave him and they lasted 50 years, but her parents never forgave him. It's not their marriage, but he was never again respected in the family. It wasn't worth it. My advice would be, don't ever try to "win" an argument. This isn't Halo. You don't unload a clip of facts into your enemies and teabag them to rub it in. Your goal is till death do you part. Stay calm, listen, acknowledge and validate their feelings. Tell them why you feel the way you do. If your spouse "loses" the fight, the relationship loses. Let them retain their pride. They won't remember a word you say, but they will remember how you made them feel.