Mr. Wonderful is very career-minded. He has been working on advancing his career throughout the years of his marriage to Girlfriend, and she has been supportive. As good Mormons, they made sacrifices so that they could live the ideal: that the husband and father would provide for the family, and the wife and mother would remain at home to nurture the children. This has been their arrangement for the decade or so since they have had children.
It only seems natural, then, that on Mother’s Day, Mr. Wonderful would take a moment to express his appreciation to his wife for her devotion to the children in particular and to the family in general. The message he actually delivered, though, was somehow wide of the mark. He essentially told her that she was an unfit mother.