I have been trying to give this matter some constructive thought, but as you say it is complicated and probably more so than you realise.
(i) Your present wife seems to me to fall within section 30 of the Family Law Act 1996. You are an owner of the house, and she is not. That can mean that she has the right to stay there, at least for the time being.
(ii) Your ex wife is a part owner of the
FMH. But I need to ask whether the Court made any financial order on the occasion of your previous divorce, because if she hasn''t, she still technically could, if she has not remarried.
Firstly, I think we need to establish one thing. The house that you live in at the moment is ( it seems ) jointly owned by yourself and your former wife. There is obviously no equity in it.
There is, of course, no law against living in a property with negative equity - as long as you can afford to maintain the mortgage payments.
So your ex wife could have a claim against the
marital home, but, as I think Cicero said, cui bono ? What''s the point ? 50% of nothing is nothing.
But I think your problems are
You are in the unhappy position that if you divorce a second time, Mrs Knaphill Number 1 and Mrs K Number 2 can both make claims against you, but, as previously mentioned, so what, there is nothing to claim anyway.
To my mind, the risk, from your point of view, is that you have a step child, and it may, just, be possible, for her to claim that she should be allowed to remain in occupation, if only perhaps for a time, to provide a home for your step daughter.
As to the money your new wife gave you to pay debts, it depends what was agreed at the time. What is your perception ?
Everything says to me that you don''t want or need a fight in Court. Some pragmatic solution which meets your needs is what is needed.
LMM