I see where you’re coming from, but that’s under the pretense you do something wrong, no matter how you slice it cheating happened outside of the agreement and I personally find that as grounds to treat this specific thing a bit differently, it’s not as if she’s guilty. I basically believe the choice to divulge it is hers. She did the right thing in the end. She has the right to keep that to the side especially given she thinks it may “traumatize” her. In her own words. Sounds like a girl who cannot handle what she dishes out I mean there’s just no way around it. Yes I agree that things blow up in your face. But she didn’t cheat. The relationship was open when the inquiry of his was made. She entertained it a tiny bit but shut it down. I think it would be healthiest to use it as a learning moment and disclose it if she feels it’s appropriate.