Well, thank you all for contributing to this conversation. It is interesting, helpful, irritating, and hurtful all at the same time. I’m not sure if my husband plans to respond, but I will state where things are at now, which will hopefully not provide fodder for my fighting, but closure for those curious:
I spoke with the gf yesterday, after our therapy appointment when my husband asked me to please let him be with her because she makes him a better person. She reported that her husband did know everything as it happened with Egoscout, but that their agreement was that she could not tell him that. So, she instead told him things like this: “Yes, he knows… He knows some, but doesn’t want to know the details… Don’t worry about what he knows, I’ll handle him. I can be persuasive…” She reported that her husband is not really OK with opening their marriage, but doesn’t want to see her cry all the time, so he said it would be OK. He said that he did not want my husband to know that he agreed to that, however, because he didn’t want him to believe that he was giving “another man permission to have my wife.”
The sorts of answers she provided led me to believe that she not being truthful. BTW at the time, my husband often thought she wasn't being truthful, but was willing to go forward anyway. However, after yesterday, I believe that she and her husband were figuring it out. Unfortunately, the way they did so made the relationship move with roller coaster motions for all of us. Egoscout, too, experienced those roller coaster emotions; he just enjoyed it more than I did.
I gave approval yesterday for their relationship to move forward, and today it has.
Thank you for pointing out my selfishness, my manipulation, my dishonesty. These are things that I will grapple with, but do not plan to do so publicly.