This is where you get into the territory of is she doing it because she enjoys it or because it's something she feels she "should" do in new relationships. We often do this. Do all sorts of things we don't or only marginally enjoy because we so very want to please our new partner. Once the relationship has ripened, then we feel confident or "cool" enough to not do those things anymore.
My view on this is very simple. If you don't really enjoy something, let's not do it. The last thing I want is someone giving me a blow job not enjoying it. Not even if it's done enthusiastically.
One of my partners asked that we try something she knows I enjoy by she doesn't like. I wouldn't do it unless we can find a way for her to enjoy it - not tolerate because she loves me.
There are situations where someone likes something with someone else but not with you. I chalk those situations up to the complexity of compatibility. Maybe my anatomy isn't well suited for that particular thing or perhaps I'm uncomfortable and it shows. With good communication, you can often determine what's the deal. And, today, I can let those things go.
There was a time when I felt slighted if a partner didn't give me their everything, whatever I liked. That's terribly coercive, even if subtly. It is one sided. It is also naive to think that our likes will perfectly overlap or that her experience will be the same (or better) with me than other partners.
So, instead, I find it much more productive to explore our sweet spot and allow that to blossom and morph as it does. Lots of day to day stuff can kill passion in a relationship. I try really hard to not let my envy get in the way of the passion that we share.
Male, Straight, Poly
“Instead of getting better and better at avoiding, learn to accept the present moment as if you had invited it. And work with it instead of against it. And making it your ally rather than your enemy.”