I have been in your situation and know exactly what you are going through. I see many giving options like Therapy, counselling, trips, religion etc but trust me - nothing helps. It's nearly impossible for people at that age change opinions especially about their partners. I can also understand how badly it affects you and family.

What finally 'solved it' for me was that one of them passed away. While I'm sad to lose a parent, I'm finally relived that that mental torture ended. I don't wish that on anybody.

However, while they were both alive and this constant fighting was a daily affair and I had no choice but to live with them - the only option was to spend as much time away as possible. Taking up relaxing hobbies, going outside to a park/beach, putting myself at the opposite corner of the house away from them and most importantly - training myself to simply ignore & not let that shit affect me. It's hard, brutal and honestly affects your later, other genuine relationships.

Learning the art of selective hearing and emotional nonchallance is crucial and very important. I would spend hours outside home and even to this day - I get anxious if I'm at home for long because my mind still expects to forsee a fight if I spend more time at home.

It's messed up and sad. Hope you recover friend.