All the above. Plus my Personal favorite, # Don't Worry About It!!!
I do have trouble with fatigue, as I am now a widow living on my own, I do have the odd nap, about 30 - 60 minutes, but rather than get up and continue my day, I find that now I just stay in my chair and don't retire to bed till 1am.
My fatigue is where my body tells me I can't do another thing, to go to bed before I end up on the ground.
I describe it as “hitting a wall” of unstoppable exhaustion. It’s not something you’re able to push through. It’s not just being tired. Fatigue is literally “I need to sleep/rest no matter what”. It’s non negotiable and often inconvenient. Tired is something you can “keep going” with. Fatigue is not.
Fatigue is where you've worked your body so hard you can't get out of bed for a few days, unless you don't mind the risk of injuring yourself. Fatigue is where your legs stop being able to hold your weight until you sit down for a short while or have a nap.