I asked whether she had a good time. She said yes. Her mother is widowed and has had a boyfriend for 5 years now. I asked about him.
Perhaps you saw this as just good manners, IDK. However, stop showing interest in what she's doing when she's out.
What you should have done is glance up at her when she came in and said, "Oh, hi", then go back to watching TV or whatever. Let "her" ask questions about "your" evening, and give her one-word answers. When you are dealing with a WAW....you don't give her that kind of importance when she's having dinner where you aren't invited.
I doubt if you can see what I'm talking about.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!