I hope this comes off the way I want it to: remember this is about you. You sound like the sort of person who is always putting others first, which is an admirable quality, but this is all about you—everyone who cares about you will immediately recognize that.

Don’t waste your energy trying to protect anyone else’s feelings. The best thing you can do for your loved ones is tell them as soon as you can (even if that means just being super blunt about it) and focusing your energy on your plan to maximize health/minimize pain, which they can all help you with.