Augh! One of my pet peeves. Control, resentment, self-reliance, career, shyness - whatever - these are possible explanations for the behavior, but an explanation is never an excuse for incorrect manners. At least 90% of the problems discussed here on DP wouldn't be problems for the letter writers or the other person if everyone learned and applied basic manners.

People aren't mind readers. Unless someone says thatnk you, how else are you supposed to know that they are appreciative or have gratitude?

I suspect in this instance that there is more going on, of course. With married couples, one person can speak for both in terms of expressing thanks. Perhaps the daughter-in-law's body language reflects something different.

Recently I let a friendship go over this very issue. My very close friend not only never had me over to dinner or treated me to a meal out, she never even offered to pay for my drink at Starbucks when she was paying for hers, despite the years (25+) of me hosting her. The real kicker is that she didn't say thank you. She acted the same way a child will with an adult relative, expecting the older person to pay and the idea of thanking them for paying not even occurring to the child. Women sometimes do this with men they have dated for a while.

Urr.