So is that the guilt trying to justify the behavior or what is that?
No, b/c women say things to the men and get into arguments with them all the time. Don't have to have an affair or feel guilty over anything. I think it's more of an "expectation" of the outcome of whatever it is the W says. That's why the look of utter confussion. That isn't what she expected you to say.
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!