Depression so deep and dark

I'm so tired. I've read some posts here and relate so well to so many of you, even though our circumstances are all different. I'm in my 40s. I had a few bouts of bad depression when I was younger, which led me to turn to drugs and eventual addiction. I've been clean/sober or "in recovery" for over 20 years with the assistance of a maintenance medication. All this time, I've had a lot of chronic, generalized anxiety along with severe panic attacks thrown in randomly for fun. Depression hasn't been an issue for me. But over the past few months I've been enveloped by the deepest, darkest depression I've ever experienced. Just total despair. No pleasure in anything anymore, and most of all, the weariness. The feeling of overwhelming exhaustion. It only even occurred to me a few days ago that that's probably what this is- depression. Naming or identifying it hasn't really helped.

I'm stuck in a not so great marriage and have several young kids. The kids existing and needing me is the only thing I live for. My husband isn't abusive, but we have some fundamental and irreconcilable differences. When we got married, we were younger and religious and thought we were doing what God wanted us to do. But the truth is we don't get along at all and haven't for years. We've stayed together for the same reason- the kids.

Almost of my family of origin are deceased, friends have long ago moved on. I can't work because of my younger kids, can't even get out to find the smallest crumb of independence, of distraction.

So, I've also had severe anxiety my entire life. The worst insomnia. Lately though for literally the first time in my life, I can sleep sometimes without effort. It's not quality sleep, but it's sleep. I can't get enough of it, tbh. The only time I feel any kind of hope or happiness even, or really any kind of positive anything is when I'm unconscious. Dreamless peace and rest or hopeful dreams. But I am so, so very tired. It's difficult to express in words how tired I am. Down to my bones and beyond. I have a medical condition that causes chronic pain and a lot of exhaustion too. It's something that sucks but I've been able to deal with. It's only been overwhelming for the past few months.

I know nothing is going to change, this day will just be like tomorrow, and it will go on and on. I've been living by that old AA adage, "just for today"....Just for today, just for the next hour, of I can make it through, then maybe I'll let myself off the hook. Just today. I do that with every hour, and every day. It's a neat trick, tbh, I recommend it if you haven't tried it before. But yeah, even that isn't really working anymore. What do you do when the despair is everything? It's nameless, formless, but it's overwhelming. Paralyzing. I just need some kind of a break.