Not sure if I have any great solutions, but I can so relate! It is the worst for me, as a teacher, when I have time off in the summer (or even on weekends), and have large blocks of time in which to accomplish things, but on many days simply can’t make a decision about what project to start. If I feel strongly about starting one thing, I always second-guess deciding to do it, because I have this underlying feeling that there must be something else that is more important to do first. And often, as soon as I decide to start something, some distraction or resistance mechanism in my brain prompts me to really want to do something totally different. I drive myself crazy with my dithering!
I have found that to accomplish tasks that feel long and tedious to me, like cleaning, sorting laundry, food prep, washing dishes, exercise, etc., it helps to pair them with something I enjoy, like listening to podcasts. (It even helps me look forward to these tasks, sometimes!) And for tasks that require the kind of attention that won’t allow me to divide my focus between both the work and listening to something else, like going through mail, paying bills, lesson planning, etc., it helps me to set a timer and plan a break (like the Pomodoro method, or some modification of it). Also, there are days, when I’m not at work, when I make to-do lists of very basic things, like make the bed, get dressed, eat breakfast, start laundry, so that I can build momentum by crossing things off the list, and, if I fail to make progress on any other projects, I at least feel better by recognizing that I have done a few things and not sat around all day in my pj’s scrolling through Facebook.