Hello danzibar: I see this is your first post here on PC. So... welcome to Psych Central.

Thank you for sharing your concern here on PC. I'm not a mental health professional. However what you have described sounds, to me, like what might be termed a kink, a fetish, or a paraphilia. Here's a link to an article, from Psych Central's archives, on this subject. The article's target audience is mental health therapists. However I think some of the information in the article may be useful:

Kinks, Fetishes, Paraphilias: Treating Issues with "Non-Traditional" Sexuality

What I, at least, find particularly of interest is the perspective the article advances that kinks, fetishes & paraphilias themselves are not "pathologized" as the article puts it. It's the effect the kink, fetish or paraphilia has on the person that is problematic. So having a kink is not the issue. How the person feels about having their kink is what's relevant. If a person is okay with his or her kink, then there's no issue. But if having the kink is causing the person to be depressed & / or anxious & is causing difficulty functioning in day-to-day life, then that is what is of concern.

To my knowledge there is not a lot of research that has been done on kinks, fetishes & paraphilias. The general consensus of opinion seems to be that there is no known cure for them. And what is generally recommended is that people who have them simply find ways to indulge them in as safe a manner as possible. So, at least from my perspective, there may be no way to know what caused you to develop your "kink" any more than it is possible to say what causes a person to want to engage in BD/SM activity or to cross dress for example. It simply is what it is. And the only thing that can really be done is to deal with how you feel about it, how you're indulging it, & what it has done (& is doing) to your relationship with your wife. And, for this, perhaps the answer is to seek the services of a psychologist or mental health therapist who has an interest in as well as specific training in working with people who have sex-related concerns. The only other suggestion I might offer would be the possibility of finding a forum website that focuses on fetishes where you could interact with others who have similar concerns.

Anyway... these are my thoughts with regard to your post. I hope you find PC to be of benefit.