I'm just going to post this MAHOOSIVE essay what I've written and then I'm going to answer what you've just posted about your tasks, because I have some, ahem, views. If nothing else, hopefully reading all of this will send you off to sleep. 
x-posts
MadBusLady I have the fog ALL THE TIME. I thought it was normal
It's not! You poor thing. How long has it been like this? The worst thing about this kind of thing is that it's not really visible to other people. They can't see how bloody hard everything is all the time.
I really, really wish I had the magic answer. I tried it all as well, post-it notes on the fridge, blah blah. I realise this isn't very coherent but eventually I started to "get better" by taking little victories. As in "Ha! I went to the supermarket like a mo-fo-ing champion today! Take that supermarket!" I got through half a degree like that and I'm about to start the other half. It did all go a bit wrong in the middle, it'll probably go wrong again, but I'm not as scared of it any more. When you're as low and fuzzy as that, ANYTHING (and I do mean like washing your hair regularly) is a major victory.
I have no idea what the correct medical diagnosis for the "fog" really is, nobody has ever talked to me about depression in a way that makes sense to me. I've never felt suicidal or had sleep problems or appetite problems or cried a lot, or any of the classic headline stuff. I just have the... fog. I can only imagine it's something in the brain not firing correctly, making simply stuff very, very hard.
Another thing, it got easier when I stopped looking for the magic answer, the organisational tool that was going to make it all right. I just accept that I need to change strategies a lot. A while back my strategy was going to the gym twice a week. At the moment my strategy is always having a tidy desk while my hard-won gluteals go for a Burton . I still work slower, and achieve less on a day to day basis than most people, certainly a lot less than I should if you look at me on paper. But it's the life I've got, and I'm very lucky to have it - and I still achieve a lot more than some people anyway. It's about trying to have a little victory every day and be ok with that, not be beating yourself up for not doing more, or better, or conforming to some abstract standard.