I don't know if this will help or not, but it is possible that your husband is suffering from compulsive over-eating. CO is an eating disorder just like bulemia and anorexia, but for some reason it doesn't get the same coverage as these other disorders. Compulsive over-eating is quite common, but it tends not to get the same attention from family and caregivers as alcoholism or drug or gambling addiction because food is legal and most everyone can relate to having a few pounds to lose, or ganing weight over the holidays or while on vacation. But two things lead me to suspect compulsive eating in your husband's case: he is unwilling to take action, which may mean he is in denial, and he is an injured veteran, which makes it reasonable to suspect that he has suffered trauma. When vets come back drinking, using drugs, unable to sleep or function or having rage attacks, doctors working with them probably assume they are dealing with post-traumatic shock and treat any drug or alcohol problems as related to the vet's attempts to self-medicate, but I bet that at least 9 out of 10 of the same doctors wouldn't recognize weight gain and all the attendant symptoms of food addiction, such as lethargy and withdrawal, that often come with it. Compulsive eating is just as real as alcoholism or drug addiction, and a lot of the same brain chemistry is involved. In many cases the two run through families, reinforcing each other, often with men becoming alcoholics and women becoming compulsive eaters -- the tendency of women to go the more socially-acceptable eating route while men more often numb pain with drugs and alcohol is another reason men are even LESS likely to get help if they are eating addictively.
I've been "around" the recovery community dealing with food and compulsive eating for nearly twenty years, and there are various debates about what approaches work best for a compulsive over-eater, but the good news for you is that if you husband is one, there are no debates about what helps the family in any case of addiction. If he's an addict, this will be affecting you and your family, and you'll need some help regaining your own balance -- some cities have meetings specifically for the partners of compulsive overeaters, but if you can't find anything like that, standard Alanon meetings, meant for partners of alcoholics, would probably help just as much if you can school yourself to hear "over-eater" and "drank" every time someone says "when my alcoholic comes home and won't talk to me because he's ashamed about how he drank at a party last night..."
Here's the other golden piece of advice for any partner of any addict: say nothing until he does. If he is caught in the snares of an addiction, he is confused, unhappy, and from time to time he WILL feel desperate to find some way out. You can help by waiting until one of those moments of desperation rolls around, until, for instance, he says "I don't know what to do anymore -- this is killing me, and I know it's hard on you too..." or "I can't keep going like this," or "I would do anything to get out of this..." In all the addictions, that's called "bottoming out" -- someone "hits bottom" and feels prepared to do anything to change. Someone still fighting with the addiction, still trying to find a way to drink or eat like a gentleman and saying "tomorrow it'll be different -- tomorrow, I'll go on a diet..." is NOT going to be prepared to do what it takes to break out of the cycle. For anyone with a spouse in that phase of addiction, the standard advice is "neither to create a crisis, nor to do anything to avert one if it is in the normal course of things." So, the fact that you never nag is GREAT. And, you may want to check to make sure you don't do the opposite of nagging, which is enabling, automatically agreeing when he says "I eat healthy -- there's no reason I should be gaining all this weight," or "if I didn't have this injury, I could play handball and that's the only sport I ever really enjoyed..." or whatever.
If/when he does express a desire to change, I urge you to tell him about Overeaters Anonymous, a 12 step program for compulsive eaters. They have meetings in most towns, and more and more these meetings all have some men in attendance (it was hard in the old days for a man to walk into a meeting full of women to talk about food, but it might help you and your husband to know that the founder of the first 12 step program for compulsive overeating in Texas was a man) . A very painful reality for compulsive over eaters is that there are TONS of different programs out there pitching to help those seeking "weight loss" that naturally attract the over-eater who has bottomed out and is seeking help -- there are online programs, self help groups, doctors, and diet books galore. And for those who aren't actually addicted to eating, those programs are extremely helpful. But if someone is eating to sooth an inner wound, then Weight Watchers and Calorie King are not going to help, because the compulsion to eat more and more unhealthy food will sooner or later become too strong. Lots of compulsive eaters go through cycle after cycle of this dance -- losing the weight, feeling great, having friends ooh and ahh over how good they look, and then gradually slipping back into the cycle of weight gain and despondency until the next diet. It is because over-eating is a problem that few in our society, either in the medical or therapy fields or even among dieticians, acknowledge or understand, that I am spending all this time laying this out, because it is a sad case where few know the facts but everyone and their mother seem to claim to have a "cure" that will give the compulsive over-eater "buns of steel," "flat abs," and a "slim, trim appearance" in less than a month. Like I said, for the normal eaters among us who truly have just gained a few pounds after having a child or letting ourselves go on a vacation or during a period of mild depression because we were unemployed, great. But for the true compulsive over-eater, all of these weight-loss programs are as if we lived in a society papered over with ads claiming to help people who are having black outs every night learn how to go out and drink socially with no negative effects. "Have a drink after work with the boys again and never, ever worry about what you may have said or done when you wake up the next morning!"
Anyway, obviously this advice is only valuable if it applies to your husband's situation. If you think that powerlessness over what kinds of food and/or how much food he is eating is at the root of his weight gain, I urge you to find out all you can about compulsive over-eating, not just as it affects the individual but also as it affects the family. I grew up with a mother who ate compulsively, as well as an alcoholic father, and I can assure you that one is every bit as serious and life-threatening as the other. Overeaters Anonymous in Houston has a website that has a lot of general information about the illness as well as numbers you can call and a list of meeting places and times.
M.