I have had those feelings of not caring if my husband slept with men, but feeling jealous if he slept with women. For me, it was about learning that each relationship in my life was individual and could not be replicated. This is something I have to tell myself all the time? Do you feel that her connections with women can't replace you? But worry that a man can?
Do you have to fall in love with all the women you have sex with? Can you accept that your feelings may be strongest for your wife but you can have other relationships too?
My husband and I both have sexual issues. There came a time when we could not solve these together and opening up to others helped us begin to know ourselves sexually. Maybe something like this can happen with your wife?