These kinds of dreams are actually very common, lots of people have them. And, like you say, it doesn't mean you really want to sleep with him, not all dreams are wish fulfillment. I guess the wife was consoling you because she knew how awkward you would feel when you woke up. Often different people in your dreams represent different aspects of yourself, so it could be that part of Jeff's personality might appeal to you, that you wish you could be a bit like that - whatever that is - then the wife might be part of your mind apologizing for trying showing you this in such a blatant, graphic way.