Me and my boys dad have been separated 8 yrs. he pays maintenance and sees them. We still have a mortage together of which I agreed to pay when he left, we have had the mortage 17yrs of which 8yrs I’ve paid alone. My ex says he wants nothing from the house as it for the children. I’m in a new relationship and he’s refusing to come off the mortage, my new partner wants to spend £40,000 renovating the house which my ex is happy for him to do but I’m scared he will screw me over. What can I do I can’t sleep worrying