There is nothing wrong with the fantasy itself, as long as you don't act it out if it has the potential to do damage.

Like already mentioned, there are other issues that need to be addressed here. I think maybe marriage counselling would be really beneficial here. I would also question why your wife has issues with it. If its something that she simply doesn't find interesting then that's fine, but it's the reason behind not wanting to that is important.

I have been with my hubby for 15 years. We used to have LOADS of sex, I mean I was sex mad. Then came medications...well simply, I just have no desire anymore. If my hubby wants to, I will...but I don't enjoy it anymore. He knows this too so keeps it to a minimum. We have learned to cope without it so much...we found strength in the other qualities our relationship has....yes sex is important, but I don't think it is impossible to have a happy relationship without it.

Basically you may have to deal with the fact your wife simply doesn't want to do it. You then have to decide what's more important to you and if your relationship is strong enough without it.

Physical contact is important to me but I get my needs met through a lot of hugs and holding hands. The sex mad girl from years ago would laugh at that.

Whatever you do, please don't ever justify cheating on her....going by what you said, I don't believe it would sit well for you and for the sake of a moment of passion, you could ruin everything you have with your wife...and it would also cause her so much pain.

Sorry I went on, but my point is, no harm in fantasy - as long as you don't act on it and also, important to figure out her reasons for not liking it and then from there you can decide what to do.