Oh, god, OP, I could feel my blood pressure spiking as I read this. It's largely irrelevant to you you should concentrate on following the good advice given above about getting your affairs in order to leave but in fact I know two men like this.
One is a close relative who inherited a house, his own childhood home, thirty years ago. It was a substantial rural house that needed some work, which is he was perfectly fitted to do as he was a carpenter and builder who regularly roofed, built and repaired houses of the same time, and had all the skills, tools and experience, needed. He had/has an extreme attachment to the house which he does not live in and worries constantly about it, and what the neighbours must think of its increasingly shabby appearance, but in 30 years, he has not done one single thing to it other than to turn off the water 'in case it leaks'. It is now falling down -- you can see through the walls to the outside, and the roof leaks, the stairs is dangerous, the front wall fell out into the road. He continually talks about doing the work, or, alternatively, selling it, but does neither. I think he's got significant MH issues, but the house has become a specific fixation on which he is 'stuck', to his wife's despair. Even though they don't live in the house, he can't go on holidays because he should be working on the house, he can't get it valued because he'd be cheated, he can't buy something because he should spend that money on the house etc. He's now in his 70s, so it's likely he'll die with this still on his mind.
The other man is a former colleague and friend. We did exactly the same job at the same level of seniority. I only realised when I visited his home and met his wife that he'd given her the impression his job was so full-on that he needed to be in the office from eight in the morning to eight at night five days a week, and to go in one if not two days at weekends, or, if not, to work in his home study while she wrangled their children, did all housework and held down her own demanding FT job.
Once she met me and realised I did exactly the same job doing three days in the office only, I could see things dawning on her -- that she'd been had for years. He'd absented himself from his children's lives to bumble around procrastinating, surfing the internet etc while technically 'working', and in fact he was notorious within the workplace for his disorganisation and his (strategic?) incompetence in key admin tasks. (Obviously I didn't tell her this.)
I'm not even sure he was consciously lying to her -- he was just an incompetent procrastinator who had never been forced to do what most of us have had to learn to do, fit work into the time available, and work, and what he viewed as his irreplaceability, had become a permanent alibi for not having to engage in family life.
So you're not alone. The former colleague and his wife are now divorced, and she's far happier. Good luck to you, OP. You don't have to go on like this.