sin, I agree with Rhapsody's explanation of why this happens. So what to do about it?

As thoughts and fantasies, these are fine. They're just more of what we were already talking about. I don't know what the mental health establishment recommends but I personally believe it's important to understand and deal with these urges.

But bringing this sort of thing into your life and relationship is problematic. These fantasies upset your wife so that alone may mean this area is something you just deal with through masturbation. Masturbation is a completely acceptable way of exploring and dealing with these particular fantasies. Role playing is also a possibility but again, not if your wife is not up to it (and please, be sure to respect her feelings with regards to these issues).

So yeah, I think the feelings are relatively common but you need to use care in how you deal with it.

Cyran0