I'm not sure what you were imagining it'd be like, I'm guessing your dh not being around and not being able to travel has made it difficult to really enjoy so its not lived up to the plan, but i do think maybe you had rose tinted glasses given the kids and you were moving house, school, country, climate. My kids are the same age and I think it'd honestly be a nightmare disrupting them, friendships, schooling, they're so settled into UK culture etc. I think you and dh need a proper chat about;
- do you fully commit to new country, if so how can he support you better, how can you support the kids more (language, friendships, counselling etc)
- do you go back now, if so it might not be that simple, would you go to the same area you came from, if not then the kids might not be happier, what would the housing situation be etc, what financial impact will it have, it sounds like dh is now office based - will work work
-do you give it 6 more months, save up for a move home, see if things do settle, see what remote help you can get for your mum, see what the schools place situation would be back in the UK etc.
- if you do need to make a decision, what will the deciding factors be, try and use as objective a decision making process as you can, so that neither of you feel it's the other forcing it- agree some definitive metrics
Moving home doesn't solve- financial strain, dh working harder, the big uprooting and unsettling for the kids (yes they'll be "home" but it won't be home, it'll be somewhere slightly different, friendship dynamics might have changed, school might be different etc). I do think it takes a while to settle, we moved with little ones so didn't have any issue from them but it took dh and I about 12 months to find some real friendships and develop a new routine, explore the area and find our new places and habits. Also, ask yourself how much of this is dh working too much and you feeling abandoned vs actually the new country. It sounds like you're quite resentful that he's settled in, and you're left behind to pick up the day to day issues alone.