OP, have you every had a sleep study done? It sounds like you may have some type of sleep apnea.
If you have never heard of it before, by all means google it. Essentially it is when you stop breathing while your sleeping and you end up gasping for air with a rapid heart rate. When this happens you get knocked out of your natural sleep cycle, which your body needs to go through multiple times a night to function at its best. Also it is very obviously bad for your heart health. Usually a common cause is being overweight, but I know of people who have sleep apnea that are not heavy. Even if you get 8-10 hours of sleep, the apnea episodes reduce your sleep quality so much that you could, potentially, only realistically be getting 2-4 hours of sleep a night.
The result is that you basically just feel exhausted all the time.
Sleep apnea is, unfortunately, something I was plagued with for years and really didn’t realize how much it was affecting me. I had a lot of the same issues you are reporting. I felt tired all the time. Could barely get off the couch on weekends to do laundry or go get groceries. General anxiety was always pretty high. A training session would absolutely destroy me, especially at the end of the day. I could do my job and train a bit but that was about it. I had to constantly weigh the cost of going out socially against the massive exhaustion the next day.
Luckily, I discovered if I slept on my side it all but eliminated it as long as I have a good pillow for neck support. Life is a million times better since figuring out the problem, and I actually have energy to build good habits.
After this I also got a buddy who I knew had sleep apnea to get his dealt with (he needs a CPAP machine). He also reported that his life is a million times better, with energy he never thought he could have.
If this isn’t a route you have explored before, I highly recommend getting it checked out.