My two cents is, she has to want to do it. No amount of pleading from you is going to make it happen. Pleading will let her know you're okay with it, but it really needs to be something she desires. Many wives, I'd even say the majority of wives, are what we would call good girls, no matter how sexually charged they are. They believe in fidelity. My wife is cool with talking the talk while we are doing it because she knows it turns me on. And she has had numerous opportunities. But in her own words, "she "just doesn't want to".