If it were me:
I'd reread what I wrote, with fresh eyes. First, I would thank my lucky stars that I have a good enough metabolism and genes (and hormones!) that I am able to look younger than I am and not have to work too hard to keep fit. These are blessings which you should count twice. For some, these are impossibilities. Hormones affect men, too-- it's not just women who go through a change near middle age. So, I'd be very thankful that this time in my life was being kind to my body and then...
....I'd realize that by comparing myself to my husband, I'm being unfair to him. He's his own person with his own metabolism and hormones and genetics. When we say "I do", we take vows to love and honor that person in all forms. I would take this to heart and be honest with myself.
Honest in admitting that, even if I don't say it out loud, my husband knows how I feel. Our words are one thing, and our actions are far more transparent. People have to be stupid to NOT notice the looks (or even, the 'vibe) one receives when they go to the cupboard and 'eat and eat and eat'. I would admit to myself that, in my behavior, my husband knows what I think of him.
I would try to see my own self through new eyes. What am I doing that is helping him to feel good? What am I doing which inadvertently cements these patterns? Silent, even covert disapproval, is still obvious and he would likely be highly aware that I'm disappointed in him. I would not try to tell myself otherwise.
I would also try to have compassion. These things don't happen in isolation. I'm going to give you a bit of insight in what I've gleaned from your past posts... you and your husband have had to emotionally walk away from your very impacted son. It might have been 'the right decision', but I'm going to guess that, in his heart of hearts, your husband has grief about this. It's a grief that might go on for a long time as he comes to terms with the fact that you can do everything and not fix a heartbreaking situation. Men are fixers, generally. They feel good being able to solve problems. This is something which, as a father, he couldn't solve.
You wrote recently, in a time of crisis, "both my husband and I are under tremendous stress - he eats when he is under stress and I have severe panic attacks, so last night while I am shaking in a corner crying from a panic attack after getting the call about Joe's most recent attack, my husband is standing at the cupboard consuming everything in sight". If it were me, I'd have a lot of compassion. I am certain, in that situation, that my husband would not look down on me for having a panic attack, he would understand that there is stress and try to be of comfort. This is your husband's coping mechanism, whether the stress is prevalent in the moment or not--it can be residual--he's still feeling it in some way. Add to that, the stress that comes with the knowing that one's spouse is disappointed in them.
I'm going to add something here from my own experience, and I think a lot of people can relate: when people who tend to easily gain weight lose it, they do tend to gain it back and quite often, end up even heavier than they were before. I have seen this with both myself and close friends. They don't always say it out loud, but I can tell a truth: many of us beat ourselves up over this. It feels hopeless that it's so hard to lose weight. It feels hopeless to lose weight and not be able to maintain that loss. That, in itself, is stressful. Hence, overeating can become a spiral. (I mean, if you're going to be worse off than you are now, it's easy to fall into the 'why even try?' mentality.) Consider that your husband is doing a lot right now, watching his grown children leave, marry, coming to terms with the fact that he cannot 'do better' for one of them, coming to terms with the fact that middle age is happening and he's not getting any younger. It can be stressful and frightening.
If it were me, as I nearly always suggest, I'd go try and see myself through new eyes, gain a new perspective and compassion for the situation. A counselor would really help. Part of the family dynamic we don't talk about often is changing our own behavior so that we can allow others to change theirs, to give them room. I believe that what goes on in my own head starts with me, so that's where I'd start. With me.