partners marriage trouble
Hi all! So I've been poly for just over a year, and have two great partners, one being my spouse. Since my other partners and I started a relationship, his marriage has gone slowly down hill. Not solely because they became poly but for a number of reasons over their 20 plus year relationship along with her finding a new partner she became monogamous with.
Its been months, the've taken of separate places in the house and barely spend time together. They have no children, yet both don't seem to want to get divorced. I have trouble grasping why they still do marginal activities, awkwardly attend family functions, and say they want to stay together despite having no real relationship. I want a little perspective because I want to be supportive...but its been a long hard struggle providing him all his relationship needs while she was continually rejecting and upsetting him. Honestly, I wonder why one of them doesn't just leave.
Any experience, perspective on a long term couple like this splitting up...but not splitting up? I get sharing finances and a home...but I don't understand how he still is interested in multiple aspects of her life when she doesn't want him, and he admits she will never be fulfilling as a primary. I sincerely hope this didn't sound judgemental and would be happy to explain more.