This is how they've acted for some time, which is what really is confusing.
I mean, she sometimes acts like that w/ her old high school friends who've moved to the Twin Cities as well - but they've known eachother since they were in 8th grade. That's different.
My W just seems/seemed so trustworthy. Not just in fidelity, but as a human being. But her flirtatious behavior with B is unacceptable. Alas, there's no way I can say or do anything about it w/o totally screwing things up for this going civilly.