I used to looooove my to-do lists. I'd use paper lists, tasks in my Google Calendar, sticky notes, lists with checkboxes in my Evernote files...anything that could facilitate that satisfaction of a) knowing every detail that needed to be done in my universe, and b) slowly crossing off completed items. I still get the warm feely feels when I think of it.
But you know what gets old? Those annoying or overwhelming tasks that ne.ver. move off of your list. You know the ones: "update my information with the student loan company," "send in IRA forms," or those completely useless ones like "figure out future." There's actually a psychological phenomenon that explains why those incomplete tasks cause stress, and it's called the Zeigarnik Effect. Bluma Zeigarnik, a Russian psychologist in the 1920s (I'd like to point out how awesome it is that she was practicing in an era when psychology was very male-dominated), observed this effect among waiters in a local cafe who were able to remember complex food orders up until the orders were completed.
The Zeigarnik Effect helps to explain the cognitive burden that comes with things we know we need to do but just can't get to. It also purports that when we get interrupted in the middle of a task, we feel anxious and actually overestimate how much time we need to complete it because it feels more overwhelming than it really is.
One thing that I've started trying and have found really helpful is scheduling my tasks instead of putting them on a to-do list. Scheduling tasks requires you to actually prioritize them in your day and fit them into your limited amount of time - a good exercise in understanding what's actually important. If you get your tasks done in less time than you allotted, hooray! You'll remember next time that some tasks don't actually require as much time, and therefore don't have to feel so overwhelming. If you didn't get them done in the time you set aside, that's okay, too - now you know that you need to simplify and try to do less (it's also a good time to practice self-compassion!). You're not a machine, you're a human with limited cognitive and energy resources who needs to rest and rejuvenate.
I know it isn't easy, but you can just start by going through your to-do list today and scheduling a few things. Tomorrow, maybe you'll schedule the work in your day instead of just making a list of nebulous things that need to get done "sometime" or in the midst of everything else you're doing. By making time for the things you need to do, you help guarantee that they'll be done and that the Zeigarnik Effect will be quieted. If your to-do list can't possibly fit into your schedule, maybe this is the time to start simplifying your life and cutting out what's not serving you.