How's your diet? Do you get plenty of vegetables? Cruciferous especially. Do you avoid fried foods? Alcohol? Caffeine? Sugar? Consuming enough high quality protein?
How's your sleep? Do you avoid eating within a couple hours of bedtime? Are you waking up to pee in the night?
I used to eat a salad every day until recently when I decided I can't be bothered to visit work canteen anymore. They gave shit food but I'd always take an extra big salad of raw vegetables. Recently my diet got worse. I used to love cooking, but now I can't be bothered, so it's instant ramen, milk with buckwheat, or potatoes + egg + bacon + fried vegetables. Not sure what "high-quality protein" is.
I had a period when I'd drink a litre of vodka every weekend, but now it's like "one beer to chill after work". Weed is my vice though, I'm stoned every weekend. I try to cut though because the amounts I used to consume now make me tired, so I'm aiming for smaller doses.
I try to eliminate caffeine, but I keep learning about new sources of it. It's literally today that I learned just how much caffeine cola has.
Sugar is my vice definitely. I cycle every day, so I burn it. When I don't cycle I hit the gym.
Sleep... it happens often that I schedule time to sleep, I put away my phone, but then I just don't fall asleep, I just lie there awkwardly in bed. Or I wake up and then can't go back to sleep. I feel like the quality of my sleep isn't there really, which is why I decided to cut caffeine in the first place. But then I sometimes have a streak where I can sleep and function well. One thing is that I tend to get sleepy in the afternoon. If I go to bed and manage to get one full cycle of sleep, I won't feel completely miserable. I don't have big meals before bedtime but often I keep snacking on something.
Whether I wake up to pee depends on how much liquid I drink before. I'd say 50/50.
I've been where you're at, and speaking frankly, if you don't make some changes, it'll only get worse. It sounds like you're tinkering at the edges but that can only get you so far.
Ramen, bacon, beer, cola, weed...
Maybe cut back or eliminate those for a few weeks and see how you feel? It's obviously way easier said than done but I can almost guarantee that cleaner living will bring back some of the lost energy, and once you've got more energy it gets a lot easier to get (and stay) on track again.
Seems like I'm doing the journey the other way around. I don't see much point in maintaining healthy lifestyle if the effort of doing so is higher than the reward. If I'm tired either way, then why bother.
What you wrote sounds like one extreme to the other. There are alternatives to beer and ramen that don't require extensive cooking. If you really can't muster any motivation at least check the canned food section at the grocery store and consider pairing with a rice cooker.
From your other comment the root cause definitely sounds psychological. I'll note that negative health consequences will only exacerbate that if and when they eventually start to accumulate.
How's your sleep? Do you avoid eating within a couple hours of bedtime? Are you waking up to pee in the night?