Try to look up info on narcissism there’s a great website called narcissism cured.com and those 2 talk of their very bad relationships with each other and healing that has occurred for both. Your description of what has happened is thought provoking. I see you both as having really deep issues that have not been resolved. Sounds like the “war of the roses” movie in your house.
What is unacceptable and MUST be fixed is the level of violence. You are both abusive to each other. The drama/adrenaline associated cements the activity in the brain as exciting and it turns into an addictive pattern with each other. This is something that must be healed. There is much hope for this. Many blessings.