The most common command from Master these days is "Go sit down." That's the last thing I, as a primarily service submissive, wants to hear.
It isn't that I don't want to do what Master tells me to but after I'm told to go sit then Master has to finish whatever I'd been trying to do.
I'm so glad I'm valued so much by Master. He has his own health problems but views me as sicker and more fragile so does as much as he possibly can to take care of me. In fact, one of my few rules is to take good care of myself. So, when I try to do too much Master reminds me that I'm supposed to be taking care of myself and usually that means resting.
To make me feel better about all of this, Master tells me things like "Go sit down and look cute" or other things to help me feel less worthless. I may not be actively doing things but at least I'm making his world more pleasant to look at.
My health conditions are chronic, degenerative, and incurable. My life span may not be changed significantly but enough else is. All he and I can do is to take things easy and enjoy what we have.
I know I have to take care of myself if I'm going to be able to do anything else but it feels so selfish to be using all of my energy on myself and to tell Master 'no' even if he's told me that's what he wants.