Hello worrywart1971: I see this is your first post here on PC. So... welcome to PsychCentral... from the Skeezyks!

I hope you find the time you spend here to be of benefit.
I, of course, don't know how old your husband is. But, since you've been married for 30 years, I presume he must be older. I'm 67. And I will tell you that I feel much the same way your husband does. The only difference is I choose to stay for as long as my wife is willing to put up with me. (Personally, if I were her, I'd have tossed me out years ago!)
I've seen a few therapists for brief periods of time over the years. They ranged from mediocre to dreadful! So I completely understand your husband's reluctance to see one. My personal view is there comes a point in life where therapists, for the most part, simply aren't interested & really can't be of much help anyway. I presume there are a few exceptions somewhere. But I haven't found any of them. I'm also no longer on antidepressants either. I've taken them in the past. But all they did was make me groggy. Consequently, for the most part, I'm just gutting it out one day after the other.
I do think there is an aging component involved here. I don't know how prevalent this is... but I have the impression that older men in particular have sort-of an instinct to just "wander off into the woods alone" so to speak. Most of us don't do it. But the instinct is there. In my case, although I choose not do it exactly, I have cut myself off from everyone else... choosing to have no friends & not even any acquaintances really. Except for the fact that I'm married, I'm pretty-much completely solitary... "wandering off into the woods alone..."
Having written all of this, I don't what the solution is for your husband. He obviously has the right to make his own choices. It's sad that he is making the choices he's making. But it is what it is. Perhaps he might benefit from joining a mental health support website such as PsychCentral... or another site dedicated more toward older adults. I have found being here on PC to be most therapeutic.
I wish you both well...