i had a heart attack two years ago and bypass surgery. i was amazed at how probably 70% of my customers were understanding and supportive and the other 30% told me EXACTLY the same thing. "you gotta take it easy and heal up........just get my stuff done first" ya, most of that 30% i wont even answer the phone for now.
as long as your killing yourself (literally) they are happy. look after yourself first, they sure are not going to