I'm not sure if this is my problem or a DP problem. I try so hard not to judge or dislike the ex as I am one myself, and I only have one side of the story. I read threads on here regularly and see this is a frequent issue. I completely bite my tongue around him and do not say anything negative about her to him when he talks to me about it. AIBU or none of my business?
Background is they have DC and she ended their relationship. Apparently he was absolutely devastated about it and shocked but he seems to have come to terms about it now and says he didn't realise he wasn't happy but is happy now. She very quickly got with a new man who has DC with him full time and IMO they are as good as living together - 80% of the week. All DC refer to each other as siblings and share bedrooms. Officially she is a single mother and complains a lot about being poor. She asks DP for money all the time for the basics saying she has no money, he pays well over the basic rate of maintenance at his agreement. He has the kids 2-3 days/nights a week too. He's a good good dad and the kids are lovely.
DP is still on the mortgage but she wants him to pay half the mortgage per month - despite new DP living there Most of the week. DP is trying to get off mortgage but she has to buy him out. She has no money so this is unlikely. He cannot pay all the maintenance and half the mortgage and his own rent but is trying to manage it all.
Here is the biggest but: he's just too nice and never says no to anything. I really feel that she is thoughtless and selfish and takes the total piss out of him because he is nice and easy to take advantage of. he feels guilty about the kids. I imagine her new DP can't contribute as he is paying living costs for a house he doesn't live in (maybe once a week). DP seems to feel like she wants the benefits of his salary to raise her children and run the household but without being married to him. Or getting a job that has a better salary. She can't move Her DP in officially without being forced by the terms of the divorce to sell it or buy him out, so it's a kind of circumnavigation of the rules. They are a 3 income family almost!
I can't see a point where we can ever live together because he's stuck on a mortgage, still subsidising her above the over the odds maintenance AND trying to look after the kids for the other 3 days of the week he has them. I have kids myself and just can't see at what point we have any future if it's like this. It feels like he is still married to her in many respects. It's very messy and makes me feel wary about getting more involved and will there be an end to it?