@Angle after a lifetime of being sick i still haven't quite figured it out but here are some possibly unhelpful thoughts

the main thing is to remember that it's a lot harder when you push yourself to your limit every single day. give yourself low-spoon rest days as often as possible & you'll be better equipped to handle rationing the rest of the time

a lot of it is also just sisu. look forward to your rest days as a way to get you through the tough times when you feel like you absolutely can't do anything else but you have to, somehow.

& this may sound obvious but figure out what tasks are actually non-negotiable, & what can wait another day