How do i ask for without begging, or making her feel bad?

How do I ask my wife for , when we are laying in bed, watching tv, I have tried kissing her, she just shys away, I have tried , feeling her up, nothing works,she has all the power. she is just not a ual person, never has, her last 2 boyfriends before we got togeather,cheated on her because of lack of . I would never cheat, but I thought with marriage, and time she would want to have with me more and more. We have sex when she wants....only......When i try to start things, I am quickly shot down. she has told me on numerous occasions, that she would never ever have sex if she was not in the mood. She has told me to go take care of it, just like that, no apology, it sounded really cold. I thought I would try it, it is not for me I don't mind doing it, but with her in the other room, knowing what I am doing is really weird. When we do talk about it, she really does not care, she knows I would like to have more sex, but she looks at me like me to do about it..help.