"However
He’s got a decent job, lots of time off ( usually when kids at school so time for himself)
I work so he’s not sole responsibility for finances
I do most house: car admin
I do most gardening
Probably equal cleaning
We have family support to certain extent
No major health issues
I have tired so hard to make him happy
I honestly don’t know what more he wants"
Yep I reckon op is a bloke!
The focus here on work/money, "probably" equal cleaning 5th on the list, re "no major health issues" are you a dr? It's entirely possible your partner has a health issue that you're either denying (having a good job etc is meaningless regarding mh issues, not how it works at all) or you're unaware of (there are many conditions where weight gain is a symptom).
"because it feels amazing after and feeling fit and strong is great" yep man! "Strong" also the focus on exercise for weight loss.
"I agree with you, some of the OP's subsequent comments lead me to think this is a man too." Yep!
"Autism also runs in families perhaps he has some autistic traits himself, that make it harder for him in daily life" good point. And if as I suspect the partner is actually a woman, I'm no expert in the field but I understand it presents differently in females and is often missed?
Luckybe40 I don't think you understand how projection works, or the difference between projection and simply speaking from personal experience.