hello there, it is possible to get over it, sometimes. It will take a lot of work, but for me it took meeting the person. I trust my partner to pick positive people to be in his life but that took some time and needed to be proved to me. The ones he loves right now all got to know me and appreciated that I am his wife and that I have some history with him. Not that I am any better than they are, but that I was someone they needed to respect as much as they respect and care for him. It just works that way for us in our relationship and quite frankly seems to work best for most established poly people. When I don't know who my husband is seeing I get that same feeling of "yuuuck" at the thought of someone touching him. The mystery of them makes it yucky for me. As soon as I see their face, experience them and see that they are worthy of him that feeling often goes away. When it doesn't, then I suspect that my gut reaction to them needs investigating.
I hope you have a good read on these forums because this very topic has been brought up many times before. You are not alone with your feelings and perhaps doing some investigating on here will help you to find your own poly way with your wife.