So, years ago they took out an endowment mortgage on this property and paid the interest portion only until now, some of which she has paid alone for the past fourteen years.
When they divorced he agreed informally to let her stay in the house with the informal (i.e. Verbal agreement not set out in the divorce legalities) that when the youngest turned eighteen she would either sell the house or buy him out.
Now that time has arrived and she is not responding to mediation requests or solicitors letters but has instead said that he should walk away from this and just sign the house over to her.
On looking into this in more detail, it appears that the endowment falls short of the original loan and as such there would be money due on the endowment not money to be paid to either party.
Meanwhile, you are married and are afraid that she is going to come after your savings as per her statement to you recently.
Now here's the thing. If there was no proper consent order at the time of the divorce, then the amounts due on the house will be the amounts as they are now. Do bear in mind there was a case recently where the ex of some rich businessman went after his assets several years after their divorce and won due to the absence of a consent order.
If there was an amount due on the house i.e. If the house had equity in it then you as a couple would stand to jointly benefit from that if he went for 50% of the value as he has claimed to want to do. As married persons you would be entitled to half of his assets, and half of his assets would include 50% of the value of that house in the event of its sale.
However, if the endowment is still unpaid and falls short of the original loan, then any equity will go first and foremost towards settling that loan before any further equity is released. Added to which, the payment on the endowment will be calculated based on the full endowment, not just on the balance over the past fourteen years. So if the endowment stands at (for instance) £100000 and has been running for twenty years, the first six years would already be calculated jointly due to the fact the couple lived in the house together during that time. If then there is no consent order in place then the rest will be calculated jointly as well, so he stands to owe £50000 on the endowment before any division of equity is even considered. If the equity in the house is less than is owed on the endowment, then he wouldn't stand to gain anything financially, but instead would owe 50% of any shortfall on the endowment, and as his spouse, you would be jointly eligible for that debt. As such she is right in that the courts may well come after your assets due to the fact that you are married to him. The same would not apply to her partner as they are not married.
He needs to seek proper legal advice, but that should also include a valuation of the property vs the endowment, because if she is talking about him walking away now that may well be in both of your best interests, and she may well not be in a position to repay the endowment at this time hence why she is stalling.
Be careful what you wish for.