I dunno. The fact that he didn't want PH to communicate with her directly and the fact that she took it so hard that they're staying together makes me think that prior to having the "I think we should break up" talk with his wife, he was promising the gf that that's just what he was going to do, maybe (again) falling into the trap of painting an idyllic picture of the future with her without trying to deal with the truth on the ground first. It's possible that she's feeling just as manipulated and yanked around here as PH. Which didn't mean she's behaving in the best possible way, but as Rose said, it's not all on her...
Of course, I could be quite wrong. I think having him come here to share his side of the story would be a great idea. The gf too for that matter.
Me, 30ish bi female, been doing solo poly for roughly 5 years. Gia, Clay, and Pike, my partners. Davis, ex/friend/"it's complicated." Eric, Gia's husband. Bee, Gia and Eric's toddler.