It's funny how no one mentions food. Or sports:)
Lack of certain vitamins or minerals can affect us greatly of course as we know on some level and yet ignore it when times are tough.
For example Magnesium. 20 years ago when I couldn’t walk for a year, of course I got depressed. I went to a psychiatrist and he mentioned that a simple thing like lack of Magnesium can cause depression. I kept observing that in the following years, because I remembered that I used to have white spots on my nails which apparently indicated lack of Magnesium. So I make sure I take it fairly regularly, preferably in natural form like Hemp seeds which are also a great source of Iron and other minerals. And in my case at least that really is a big factor which influences my mood and state of mind hugely.
I have two out of four step children living with us now. At first they were depressed and sluggish and all that you were describing. But then I figured out how they like to eat potatoes. And chicken. So I made sure I made them fresh potatoes and fresh chicken and added lots of spices and herbs and a couple of things like turmeric and a bit of sea kelp (iodine) because I use unprocessed sea salt and there is no iodine added to it. Oh, and I could introduce garlic with baked potatoes (I put whole cloves of it in the oil) and a bit chopped up in the chicken or meat or veggies as I prepare the food.
I also always make sure there is fresh orange juice in the fridge which seems to be a big hit.
You see, when you're in a lockdown and unmotivated somehow, well, at least I started to reach out for food that would make me feel good, at least for a moment. Comfort food. But we all know, chocolate and crisps and chips and all that crap doesn't have any nutrients that we need. Which then only contributes to the low energy.
The kids had a massive growth spurt and stopped sleeping so much, are laughing and in a good mood now, bugging us adults sometimes to make fun of us for hours (this is when I wish they would just go back to sleep, lol. Only joking.) and despite the fact that none of us can go out, there is a general better mood.
You can try and motivate the hell out of yourself but if you are not looking after what you eat and the chemistry of your body is simply lacking, then I think no amount of motivation in the world will help:)