For me it was a combination of things. Cultural issues and then later religious issues that left me with mental blocks regarding sexuality. For me, it wasn't that I didn't do certain acts, it was that I was a little ashamed for doing them, and enjoying at the time. For example, girls who performed oral sex were labeled as fast or loose growing up and sex was a taboo topic among adults, so I learned about it from the wrong people.
I had to undo these mental blocks. I did that by being honest with myself and searching for reasons I felt certain ways about certain acts.
Then by reading up on male and female sexuality. And most importantly, as silly as this sounds, giving myself permission to fully enjoy a healthy sex life and whatever that entails.
Also having really open conversations with my huaand about these things even before marriage. Many of these discussion were sparked by pre marital counseling, but then I had to keep working on them. Just talking about it is one thing but actually applying it is another.
I would just keep encouraging your wife by making sure she knows you won't judge her, and starting discussions. But ultimately, she has to acknowledge that she has hangs ups that she wants to overcome, which it sounds like she has.
