Yes, was in almost exactly the same boat (not in a different country to my own though).
Had to stay in that situation for a year, with him being rude and obnoxious as you say, because he knew financially at the time I couldn't leave.
I slept in the spare room and spent every evening either sitting in my room, out walking for hours, or sitting in my daughters room with her playing games.
I survived it by being polite and biting my lip. Keeping it decent and avoiding rows at all cost in order to maintain harmony for the kids. It was ridiculously difficult to do but I'm a changed person as a result. It was one of the hardest times of my life - felt like a prisoner in my own home. I used to dread even going home and my heart would sink if his car was on the drive.
I kept sane by knowing I would eventually get out. I made little plans like went on a shopping trip and secretly got myself home essentials - cutlery, a kettle, plates - and stored them in the garage.
When I did eventually find a private rental to take me on, I took about a month getting it ready gradually so me and the 4 kids could just move straight in. Broadband connected, beds put up etc. So we could all just 'go' one day without stress. We took no furniture only our belongings.
It was such a miserable time, I felt absolutely desperate at times if I'm honest. But you will get through this and life will be wonderful again.
All the best.