Ya it's hard. Something that helped me was the realization that doing manual tasks for 2 weeks converts them into a habit.

The first thing I'd recommend doing is writing out everything on your todo list. This is just a flow state thing, I don't care if one of the tasks is "put pants on today" or "make my bed" or "remodel the bathroom". Just get at least a dozen (maybe even 100) tasks written. Stop reading here until you've done it :-)

Now go through and tag them as: Recurring, Soon, Tomorrow, This Week, This Month, This Year. Or whatever timescales you prefer to think about. Also give them a rough estimate like 5, 10, 15 minutes, N hours, etc. You can also rate each task on a scale of 1-5 or 1-10 for how urgent they are to you. It might help to move them to the rows of a spreadsheet or use an app (I used Google spreadsheet).

Now you can sort your tasks by column in various ways, and SUM() the estimates to get an overall idea of how long they will take to complete. You can also begin breaking tasks up into subtasks. As a rule of thumb, each task can be separated into lower timescales. So days to hours, hours to minutes. If that's too nebulous, just mark unknowns as TODO.

It helps to reflect periodically on what you are dwelling on, and work to get it out of your head into the TODO list. If you're thinking about it, write it down. It's ok to let the list build up over a few days. This is your time to recuperate and heal from burnout.

At this point, I used the 3 second rule as motivation to do something. The idea being that the body can't perceive the difference between anxiety and excitement. If something caught my fancy, like I could at least gather the papers on my desk into a box, I just did it immediately. Cross that off the list. Sorting could be postponed till later.

So rather than dwelling on brushing my teeth for 2 hours after my girlfriend went to bed, I brushed them immediately after tucking her in. I basically assumed that I had no working memory, and that I was an automaton following a script.

Checking items off the list helped me move up through levels of abstraction. I kind of went from the seconds timescale, up to minutes, hours, and finally days. I realized I had been so knee-deep in my work over 4 years that I had put off like 1 year of chores around our property. The things that seemed so insurmountable (like brushing my teeth) gradually moved from my conscious mind back to the subconscious. It also helped that my girlfriend kept me on task but understood that it was a process.

You can also add in new recurring tasks that don't take effort, but might have been weighing on you for some reason. Things like: going on a 20 minute walk each day, meditating for 20 minutes a few times each week, remembering to eat every 3 hours, taking your B vitamins, etc etc etc. Control the things you can, so you can work up to things that feel outside your control. I strongly believe that as you get your recurring tasks back into your routine, you'll feel a lot better.

The term for all of this is "executive dysfunction". It's getting really common in young people because we're so saturated with multitasking and interruption that it's shortening our attention spans. And in my case, I was trying to hold these huge problem spaces in my head too for work. So my motivation was completely exhausted day in and day out, and I couldn't even manage to do something as minor as getting a letter in the mail (I'd put it off for weeks).

But ya, as I climbed out of my hole, I started realizing that much of my burnout revolved around an emotional issue. Cleaning my home office wasn't the problem, going through 10 years of old bills/paperwork and reliving some difficult times in my life was. I guess I had hoarded that baggage in my mind. You'll have your own insights though.

And it will absolutely get better, even though it feels rough right now. Just move at least 1 step forward each day and you WILL reach your destination.

Edit: I forgot to mention that I don't have to use my TODO lists anymore. I do use the iOS calendar app, or jot things down occasionally in Slack, but it's few and far between. So put aside any worries of lists coming to dominate your life :-)