cp1970, I've followed your thread since you started it; I think you write well ... very descriptive & detailed. Normally, I don't let myself get involved in continuing threads because they're sorta like watching a TV program that says "continued ... ". You miss an episode, get behind, and find yourself out of sync with what's going on. I would like to toss in my opinion, however, if I may.
I think there's a lot going on in your woman's head right now ... frustration, desire, etc ... lots of confusing emotions. On top of that, you've mentioned more than once her sensitivities with sex during her menstrual cycle. I'm thinking that actually has more to do with those highs & lows than maybe you or her realize. Menstruation causes chemical imbalances and affect different women in different ways for sure, but, they also affect the same woman different ways each cycle, plus she's got a lot rattling around in her head ... I detected she's confused with you, she even seems to be confused by herself and her own emotions & thoughts. I've said this more than once, women approach sex differently than men ... they look for the emotional benefits of sex that men don't necessarily need just to have sex. You're basically denying her of that ... wanting her to follow through with a physical encounter but restricting the emotional involvement. Women usually have problems with doing that.
You need to help her regain her balance of confidence. You eluded to it several times ... bragging on her looks, etc. I would continue doing that. Taking her out to functions where she can dress up a bit and look sexy, and continue reassuring her as to how important she is to you. I'd lay off the encouragement of her hooking up with someone for now. Your agreement with her even confused me. If I were female and in a sound relationship with you, I'd have problems with having a physical relationship with an outside party, as I wouldn't be sure how you really would react to it.
She's been denied physical experiences with other men to this point, and she's super curious to explore right now. She is going to take that next step and I wouldn't be surprised if she took it without your acknowledgement.
I'd work on firming up your relationship with her, first ... maybe come back to the cuckolding later when she's more stable. Good luck ... Mac