I would go ahead and follow some of your interests like the cooking or crafting. They will keep you busy AND provide you a sense of accomplishment and worth that we so often need when depressed. The potential to enjoy yourself is a bonus.

It's hard for me to tell if your spouse is similarly depressed or just being who he is. How long has he been this way and did it happen all of a sudden?

I suppose one way to tell might be to find out if his mood ever gets dark in addition to the lethargy.