Wow, thank you so much for your advice! It feels great to have found some support in this arena. You all pose very great points
I am so the opposite to him in this line of thinking. I would feel so excited for him to experience another love or intimate relationship, I know how fun that can be. Also, it may be worth saying, I am his one and only. We met when he was 24, never been kissed or dated (he was shy, but really hot, go figure), so I swooped him up and he never doubted our love. I dated A LOT before him, so I knew what a keeper he was. I always felt bad that he missed out on all of the sexual diversity there is in the world, all of the adventures to be had. I understand he probably won't change his mono status, but by putting myself in his shoes, I try to better understand him and help him translate my own feelings in that situation.
Who knows if this will ever go down, but you are right, thank goodness he is kind and listens well. He understands this is how I feel (whether he believes the solution is sleeping with other people or not) and validates that, to an extent. Our marriage is in no way over, and if any one has a shot at surviving a mono/poly relationship, we would, if he can wrap his head around it.
Thanks again and keep it coming! I will be sure to read up on it some more!