I think you need a reality check here.
most likely Mobile, he will go back home to his wife and you will remain in the UK with a broken heart and lonely.
Or, he will stay in the UK, will divorce his wife and feel guilty about it for the rest of his life.
Or, none of this will happen, I guess the time will tell

Both of you are not doing the righ thing and you are both parners in crime.
He is judgeling 2 women already, so are you willing to have a commited relationship with him in the future? Do you want to have a family and children in the future with him?
Or you just having fun.
Fun is good, but at one point we need to take time to think where it's going, what is our part in it, what do we want out of this and are we willing to make sacrifices.
I migh sound like a moral know it all, but life has it's requirements and it usually corrects itself in a long run.
Unless it's love.
All the best to you