Hey mate that sounds very hard and it also sounds like "each of my parents" whom were very damaged people each with unresolved trauma. The kids of the family ultimately were deeply affected with deep personality issues, at risk of dictating your life I would ask you to contemplate for your own future:
-What are the benefits of staying?
- How would you move into an independent life?
My Mum did NOT break the cycle and now her two sons are each misogynists and abusers in their own way as they learned from their father "how to have more power" only they didn't learn to generate the power of aptitude and respect, they learned how to have the power of tyranny and dishonesty and it's fairly sad to see. I am a female and I learned to have no will, no self esteem, no self respect like my mother and got walked all over for the first 35 years of my life.
Thus I would urge you to look at the fact IF your partner won't resolve his trauma and learn how to behave and interact like a normal person, thats the point it becomes an imbedded personality variation and, how much energy do you have to manage an extra child in an adults body or is it to the point where that adult faces the consequences of their own choices, or lack thereof in life. As life is quite difficult enough and when we are adults there's a lot of things required to function in society, as an adult there's not much room to go backwards nor people to make excuses for us.
And I watch my mum still making excuses for her sons which all come back to "they learned how to be demons from their father and I am still fighting demons and playing a martyr game" but our family has never even been on a holiday together due to all the time and energy, and money being wasted on dysfunction. It's like paddling in a dinghy or driving a nice boat, having a psycho in the family is sorta choosing to paddle the dinghy when everyone else is sailing along in a boat with a motor.
I dont say this to upset you but to hope that you find the strength and clarity of mind to say 'enough is enough' of that behaviour. Be well and safe over Christmas.