Today I got a molar pulled. It was an easy extraction: no incisions, the tooth popped out with little tugging, and no stitches needed. The oral surgeon sent me home with a wad of gauze in my mouth to stop the bleeding. I stopped in the pharmacy to pick up my prescriptions and at the post office to pick up our mail. Along the way I chose to nod my thanks/acknowledgement to those who held doors for me, etc. I could speak a little, but hello: I had a gaping hole in my gum from having had a molar pulled within the same hour. Better to not expose that to outside air.
I wonder how many people walked away from my thankful nod thinking, “How rude of her to not say, ‘Thank you!’”
This is why I give people the benefit of the doubt. You never know what’s going on with them.