There's a bipolar rhythm of life and work that's easy to fall into, but it sounds like you need a break. There are very worthwhile projects that might take only 10 - 20 hours a week that, if you live simply, will be more than enough to get by. You can learn a lot from introspection in the remaining leisure time. Make sure you've got your necessities taken care of: shelter, learn to cook, get exercise, sunlight, make sure to hang out with friends or at least someone twice a week.
Sure enough you'll have the motivation to work on something again, maybe big, maybe small. People aren't built for leisure, but enjoyable work.
Yes, I have got the "bipolar" part, no so much the "rhythm" part though.
But seriously, I see what you are saying. I have always been a all-or-nothing kind of person, but maybe I should actually try this work-life balance thing that I have been hearing about.
Sure enough you'll have the motivation to work on something again, maybe big, maybe small. People aren't built for leisure, but enjoyable work.