Vanilla husband kinky wife

So my wife has asked me if I wanted to open our marriage up. And I was hell yeah at first. Now I am having trouble finding a play partner and my wife now has a play partner and I don’t like it. Since I don’t like it and I have told her she tells me it’s something she needs.

She is about to enter into a D/s relationship with a guy that I have never meet. Spending a lot of time with him and I feel like I am on the back burner. She tell me that I have to earn sex which I think is wrong. I shouldn’t have to bow down to her every want. And just because we don’t see eye to eye she won’t give it up. How many women hold sex over the SO head.