Donothingism... I like that term. It's so perfect.

If it helps, you're not the only one who feels like that. I'm a student, and I've had to get my counsellor to inform all my academic departments that my donothingism is due to medical causes and as such I might not always attend class (they're SO strict about that at my school...) On my "nothing" days, I will lie in bed and think about all the places I should be and all the things I should be doing, and it just makes me feel defeated before I even put my feet on the floor. The donothingism or laziness is definitely caused by my depression though, which I only started to recognize when the meds kicked in and started giving me days when I COULD get things accomplished. Eventually, I've come to realize which difficulties are related to my depression, and which aren't, and the distinction makes the depression a lot more manageable. Maybe you could do the same? If you can start believing that it's the depression giving you this donothingism instead of just being lazy, it might put your illness into perspective and give you some fresh ideas on how to fight it.

Sending lots of hugs. Be good to yourself, I know it's hard.