Doing trading online is stressful for me because I can't just relax and play the game while I'm trading or waiting around to be available for trading. Running a thread takes up a lot of energy I can't be bothered with most of the time.
Everything else is just like... chores, but fun and relaxing. And I try not to put too much on my to-do list. Like, grinding for villager pics with the wrapped foreign fruit, that's a thing that would add to my daily load that I simply choose not to do. That means less on my plate. I don't have a quota of Nook Miles + achievements to fill every day either, I just let whatever happen naturally. And if I stop halfway between something to do something else it's okay.
It's funny, I know what you're talking about and it happens to me with stuff I need to do in real life (because my ability to manage time basically doesn't exist and I don't know which thing to do first and I can't multitask effectively and anxiety happens), but never in this game. Maybe because I know there aren't consequences to not doing things on time?