Hey GB90. Being a guy, fantasizing about a threesome with GF / W and another woman is fun... I know that is something I would not likely ever do.
Good for you for finding your way here and being brave enough to post your situation.
I will first say that I am NOT open to an open marriage. My W suggested that I find someone else to see if the grass was greener. I said, "no thanks. I am sure it is not." First, I am sure it is not. Second, I have no interest in enabling her to have her own PA. Third, I do not care if it makes her mad that I do not seek elsewhere and "leave" the M in that way, because I believe in the M vows and covenant.
Be true to yourself in this one (of course, always). If you have to "dig" to find it in yourself to have an open M, then you are probably fooling yourself if you think you can. I actually found myself in a position to have a PA... and I broke down... nope... not for me.
How would your W define "open M"? Is it necessary for you to have a physical relationship with someone other than your W?
"Guy fantasies" aside, what would your feelings be if she would physically be with someone else? Your first reaction after the "woohoo" is probably the true one. And re-think it but put your W with another man and see if your feelings are the same.
If your reaction would be one of "nope, don't like the idea", then do not accept it.
Unless you said your vows as "I will be very happy if you have intimate, physical relations with other people once we're married", then you likely vowed to be with her only and expected she stated the same. Bi or not, when we say those vows, we vow to be monogamous.
