You have to talk with her bro...she has to know what you like. Sex is the most important thing in a relationship. If you don't have what you like, probably you'll find it somewhere with other person. And i think that bot what she wants. She can't be selfish. Even next time she go to the gynecologist, go with her inside the room and aske the doc for a hormone levels test for her. Maybe she doesn't have enough libido the get that wild side in the bed...
good luck bro!.