Fatigue means that I cannot organize myself. Can't pull myself together to do specific things, in order. Just halfheartedly try to do a few things and give up for a while, unfocused. Unfocused mentally or physically.

Like having cognitive dysfunction that affects the whole body. And it can be bad enough so one cannot remember that one will come out the other side of this. Of one faintly remembers this, and therefore lies on the couch staring balefully at the television.

I think it's important to note that, fatigue and depression sometimes
go hand in hand. Talk to your Doc, if you haven't already, about
an AD that may also have a bit of an upper effect, such as Prozac.

Be careful though, I take Prozac now and I love it, but couldn't take
it years ago, when I suffered from anxiety.. I think LDN also helps
to curtail fatigue...IMHO.

Fatigue (for me) is when someone has let the air out of my tyres, and brain fog rolls in so I can't move fast, everything about me (including my brain) is in slow motion - while the rest of the world is at normal speed - and nothing computes, except a feeling of hopelessness and helplessness when it's really bad.

I almost feel disconnected from reality. I stumble through physical movements like a drunk, trying to communicate using words that I can't seem to find, and thought processes that I can no longer put into any semblance of order, with little retention of information.

And it can come on just like flicking a switch - no warning - just bam!