Giving and Receiving Oral

Me and my boyfriend have an O.k sex life . But something that really bothers me is that he won't go down on me , but he's expecting oral all the time. I've tried different things , like talking to him about it and requesting, giving him an ultimatum, and trying to make things more fun in the bedroom . I keep things clean down there , and I shave but he still avoids it. It's gotten to the point that I don't enjoy giving him oral and I avoid it all costs. I'm at the point where I'm about to end our relationship. Has this happened to anyone else ? What should I do ?