I feel you,
@honeybbq. My wife is similar to your husband but for different reasons. Honestly, I haven't found a great solution. You really can't make another person want to change. However, there are some things you can do to help make your space comfortable and livable for you.
-Focus on your own stuff. Get rid of as much as you can on your own. It can serve as an example, but don't count on that. The bottom line is if you get rid of more of your stuff, you will have less stuff.
-Work together with your husband to figure out storage solutions. No, storage is not a replacement for decluttering, but it's still better than having stuff sitting around if he's not going to get rid of it promptly. Boxes for things to keep, things to sell, things to donate, things he still needs to go through. Then he can just pull out one box at a time. His time management might be better if he has a focuses set of items to deal with in any given session.
-Be vigilant about keeping your house clean. Somehow all the clutter seems less painful if the counter tops are wiped down, the bathroom is scrubbed, the floor is swept, etc. I used to put all that stuff off because I was daunted by everything I had to move to do it. Which is where the storage solutions came in....If you don't already have a good cleaning routing, I would recommend a blog called Clean Mama. I forget where it was recommended to me, but she breaks down weekly cleaning in a way that finally clicked for me. I can still make a lot of progress even if I'm having to move some stuff out of the way.
I still think we have too much clutter and would change some things if the space were just mine, but I've finally reached a point where I feel okay in the space instead of fantasizing over apartment listings for one person. In your case, I wouldn't worry about paring down too much. It sounds like you still have so much stuff the overflow is getting shoved in closets, so I don't think your house is in danger of not feeling lived in.