I don't of course know specific details of your situation, but I would appeal to his sense of empathy.

After my stroke, I would get very emotional at the drop of a hat. I would laugh, cry, or get angry over nothing. I once snapped at my wife while she was driving; she took it very personally, and I nearly shouted at her, "Don't you understand? I cannot control this!" Luckily, I recovered past that phase before she ran out of patience with me.

Could your husband learn to limit his venting in your direction? What is his point in unloading on you? Does he think you can fix the world's problems?

It also seems to me that he'd be better off if he'd quit watching the news and read some classic literature, or sci-fi, or literally almost anything else. The media's job isn't to inform, it is to keep you watching, and their main tool is fear.

I learned this myself the hard way, years ago. My wife finally told me, "Enough. You're obsessing over things you can't influence. Stop it. You're making yourself crazy -- and taking me along for the ride. Just...stop it. If you won't do it for yourself, do it for me."

She's a very sensible woman, so I paid attention.

Does that help at all?