Have you talked to a solicitor. It's entirely possible that your wife could stay in the family home and that you'd have to pay her maintenance and you'd only have enough left over to rent a small flat. It's not an uncommon situation for men (in particular) in your circumstances. You are trying to come to an arrangement whereby each spouse has a family home, but you've not posted up the figures to see if this is doable. Also it's not clear what your wife actually wants. What she is saying to you may not be what she is thinking of doing.
I don't think you should get your dad involved in this mess. The 3 rentals are his only income. His involvement would be unfair on him and no doubt a solicitor would advice him not to become involved.
I realise your not in a good place right now, but arguing here about the rights and wrongs of the banks view, well they don't care about that. It is you who have to demonstrate in figures, not emotions of maritial splits that you can afford to get what you want.
Can you afford for her to stay in the house and you to rent somewhere, while you pay her maintenance, or vice versa. But I fear if you force her to move out, she will make the ultimate move to the UK. You are going to have to think through every option very carefully not just the preferred option. It would be far better if you both would talk and decide what can be done and who is willing to do what. Very difficult, sometimes impossible. There are no winners, and better to make the choice that is in the best interest of the children.
Sorry now for being tough, but being nice is not going to help you. You really need the advice of a good family solicitor.