@TheLizardQueen
I'm telling you that a little flat on your own is paradise compared to a house, even a palace, with a man like that. My marriage ended for other reasons than yours will be, but having my own little place where I am truly the 'Queen of Everything' has been a revelation. I am happy and at peace.
First, get legal advice. You are the main breadwinner so in a way you're in the catbird seat. I'm assuming that you earn enough to support yourself whether in a flat or the current house. So, see a solicitor, find out what's what. Take a snapshot of your and his incomes and family finances; monthly costs, mortgage info, other debt, etc. With this info a solicitor can give you an idea of what to expect financially.
You only have 5 years left on your mortgage? Hallelujah! If you aren't able or don't want to buy him out then there should be a good amount of equity (split between you) to give you a fresh start.
He's not violent, so you have time to get your ducks in a row. In the meantime, grit your teeth, take a deep breath and start to carve out your own life until you can leave. Do things on your own, even if it's sitting in a park reading a book. Join a club, take a class, anything to get you out of the house on your own. If you can, get away by yourself. Is there family or friends you could go visit (alone) now and then, even for a weekend?
You have many many years left. You deserve to live them in happiness.