Well....now I am glad you don't work with this person any more...even though they are retiring. I get that you were just too tired to fight it...and I think you are right that it would not have been worth it.
I do tend to save my gory details for these folks. I once heard "aww honey you just are tired and that's why you have a tummy ache"....my response...a "tummy ache" does not come with your guts tearing themselves apart and being less than 12 hours from a septic coma....but thanks for being so caring." But, I am usually much more passive and say "Crohn's is not as simple as TV makes it out to be...I could tell you more if you want."