Sowhatnow was the closest. I know this from personal experience. She is embarrassed that you don't go with her, and she feels lonely. She sees 'everyone else' supported by their husbands, sees complete families all together, but she sits there alone. She thinks about it on the lonely drive home and gets mad at you for doing this to her.
I would suggest planning something to do together after the meeting, maybe take her out to lunch Sundays when she gets home, like you probably used to do when you were both going.