Hi OP,
Does the country have the equivalent of small claims court?
Here in a small business (unless it was a limited company) the owner would be personally liable so their house, personal savings etc would be assets that could be drawn on.
I think the huge financial stress you are under makes it hard to see the wood from the trees regarding your relationship. Why not wait to see how it is when your finances are more stable whether in the UK or wherever.
Personally I think you should try to take the rough with the smooth and not bale out of your relationship because your husband is struggling. Perhaps it is your turn to be the main earner? Why is it OK for your earning to be limited but not his?
It is an enormous life changing wrench to have to leave somewhere you love, but if you do have to you won't be the first.
Does your very small house only have one bedroom? I'm wondering if you have lost perspective and it is, in fact, a fairly ordinary house?
It sounds like your husband is now struggling with his mental health (when you say you have to help him with everything) so it may be that you do need to move back if you can't support your family and the country you are in don't have a safety net to help you manage. (do they?)
My husband had to take a step back and go part time due to stress at work when I was a stay at home mum and ever since we both work. I was only ever concerned about him and feel I have an equal responsibility to provide for our family and it was my turn to step up. I also had to leave an area I loved and hoped to stay in due to this change. It was tough and life changing to accept that that dream wasn't to be but sometimes we don't get the life that we wanted. It is tough but for us there have been compensations like being near grandparents. I think your family needs you to be the strong one right now and make some decisions.