I've only read the first four pages of this thread, but will return to the rest later.
I wanted to post my own story as it's different from others on here, so I'm hoping it might help or encourage people who find themselves in a situation similar to my own.
I was living outside the UK when I decided to leave an abusive relationship. My exH is not British and my DD had been born overseas in his home country, so not only were there a lot of potential complications, but also I didn't have a great understanding of the law in that country. The country concerned is very patriarchal and women tend to put up with whatever shit their husbands throw at them, so there is little in the way of support for victims of DV - they would simply prefer not to believe in its existence. (Things are slowly starting to change if you're lucky enough to live in the capital city, but that's another thread.)
Leaving my exH meant I had to uproot my DD from the only home she'd ever known and return to the UK with no job or home to go to. I was aware that if we left, her relationship with her father would suffer, which was a hard thing to come to terms with. I was effectively removing her from a huge family of aunties, uncles, grandparents who all adored her, and whatever I thought of him, he was still her dad. The catalyst for me finally deciding I had to leave came when he hurt her, too. Not seriously, but enough for me to fear escalation.
He did not make it easy for me to leave. I had no money of my own, so sold jewellery, books, anything I could to raise the airfare. I told him that if he argued with me and prevented me from leaving I would move out of our house anyway and tell his parents about his behaviour. The law of that country meant he would have had to support us financially if we'd stayed, even though culturally it's very much a man's world, so I think that helped him decide to 'let' us go. It would also have given him an opportunity to portray himself as the injured party.
I was unable to take any possessions beyond a suitcase full of clothes for us both. I didn't even own a duvet or a saucepan when I got back to the UK. I knew my parents would offer no help at all. Again, that's for another thread, but I didn't expect support from them and none was offered.
In the UK I had to try to sign on, so that we had some money to get by. I had only been able to bring £530 out of the country with me. I had to pass a habitual residency test before I qualified for benefits, despite being born in the UK and being a UK taxpayer for fifteen years before moving abroad. We lived on friends' sofas, moving from area to area for four months until the local authority gave us a hostel place. Once I had a 'home' I could start to think about working again.
My DD sofa-surfed for four months and lived in a hostel for eight months, but I had never seen her happier. Throughout all of this, I was being treated for MH issues (depression/anxiety), but I never lost my focus on providing a better future for us.
It was hard. Sometimes things seemed unendurable and the responsibility of thinking about how much I had changed my DD's life materially often gave me pause for concern, but I never really had any doubt that I'd done the right thing.
My DD is a happy, sometimes bolshie (normal!) teenager, just starting her GCSEs. She doesn't remember being homeless or living in a hostel (she was 3 years old), but she does remember moving around a lot as a child. Her father's contact with her is patchy. He has never paid a penny to support her and she is now old enough to have worked this out herself. He never misses an opportunity to tell her how shit his life was with me.
He also had dishwasher issues, BTW 
, which could enrage him so much that he would resort to hair pulling and pinching. He threw things around a lot, too, but never actually hit me. He was emotionally distant and thought nothing of not talking to me for months on end. I would wake up some nights and find him trying to have sex with me when I was asleep. He drank. He told me that I should learn to control my behaviour so that he wouldn't 'need' to get angry.
If anyone else is living overseas and wants to leave, but dreads coming back to the UK and having no job, home or income, I want to tell you that yes, it's hard - especially if you don't have a supportive family here - but the benefit to your DCs will be enormous, the relief you will feel when you are no longer abused will be immeasurable. You will be happier in the long run. It can be done.
This organisation rights of women helped to advise me on legal issues when I got back to the UK - all free of charge.
Sorry that was such a long post!