I made one of those horrible remarks this weekend. A grandson had taken his cousin's advice on what to wear to a party and very inadvisably dressed. I said, "I can't believe you listened to her. She's not even married!" Meaning, a single girl doesn't have the experience a wife does. However, it was a classic moment of open mouth and insert foot. I felt horrible. What was worse, his cousin had just last year gone through a horrible experience of having to break off an engagement with a man she loved but who was just not ready to commit to doing anything but telling her what to do and when and how to do it.No one could believe I had said that, including me.
I hope it is explained by the vagarieties of old age.