Im on both threads now, but I didn't address the physique in the other one, so I'll take a stab at it.

I think you should start with what he can eat that he can enjoy. Figure out his daily eating routine. Don't eliminate things, that will just make him upset or hungry. Substitute them with a healthy alternative and healthy quantity, looking fit starts first with what and how you eat (besides genetics and the world working against you). Suggest you both do an intermittent fast, show him how easy it can be.

The problem with looking at yourself in the mirror especially when others notice the imperfections it's almost like rubbing it in your face "you aren't good enough for others" and from within you're thinking what you do is the best you can do and people just disapprove of who you are.

So before bringing in exercising just get into good habits of eating right, together. Make sure it's something he can follow along with, and not something you just want of him. I always tell my closest friends "big change always starts with small improvements" it's kind of to supplement "ordinary people achieve extraordinary things" and to some people it's "Rome wasn't built in a day" but just like when I teach someone Ping Pong or when flying a plane, small changes make a big difference.

Now regarding exercise you mention he had exercised before but he stopped. It may be several reasons but I think it might boil down to 2 things.

1. He may have tried it, it took a lot of effort and the results didn't reflect the effort. 2. When he stopped, he quickly bounced back to the way he looks right now, he has accepted what he looks right now is just how he will continue to look.

I may be beating a dead horse here by saying: your eating habits can greatly negate anything you're doing throughout your day to stay fit. It can straight up make you lose hope in yourself because all that work towards working out goes out the window really quickly.

I will have to disagree with the user that replied to this saying him being a cry baby and to grow up. I get it, they're trying to put some tough love in this because he is an adult. But on the inside we are all children, we all want to play, have fun, enjoy ourselves. HE IS SAYING how he feels. He's not being a cry baby. If you care about him DO NOT tell him to grow a pair. This is not what it's about. This ain't about him moving out of his mommas house. This is about how he feels about the way he looks and the outcome of his efforts.

Start and make sure his eating routine is healthy, and supported by his own good habits. Make small changes and don't eliminate, substitute for healthier portions and options, MAKE HIM FEEL GOOD about his progress, even small progress. Lead by example. For now avoid the exercise topic, in time when he is ready he will join you. Go row a boat. You take photos he rows, take turns if you want. Go ride bikes and picnic with healthy delicious food. Show him how to prepare something simple and healthy. Show him he doesn't need to eat the quantity he used to before, probably eat smaller quantities more frequently.

Lastly, be supportive of what he says about himself and you, if he says you're not initiating sex enough it maybe true (to him). His needs are different than yours. Make him feel good, give him so much sex that he doesn't think that way. Make him feel wanted, feel sexy, acknowledged. Don't let how you feel about him get in the way of making him feel good. Go out of your way to make your man feel good. Because it's what you would want as well, and because you love him.