Attracted to women but want to dress up and pleasure a man

I'm a male and I've always been attracted to females but I've had a fantasy about dressing up as woman and pleasuring a man for most of my life (I should say an obsession). I've been putting on women's lingerie and other feminine clothing items since before puberty. I'm married with kids and love having sex with my wife but this fantasy has been growing stronger and stronger to the point where I'm afraid I'm loosing control. I've never acted out on this and don't want to because I know it is wrong.

Most of these fantasies are romantic and sensual - I most often fantasize about a mature man or more frequently a mature couple who would like a third. I like to think about presenting myself to him/them in lingerie like a bride on her wedding night and having full sex. I always picture myself doing everything a woman would do during sex. And I love the thought of seducing a man/couple.

I act out these fantasies alone in the privacy of my home but usually feel extraordinarily guilty afterward - to the point of self harm and other destructive behavior.

But as mentioned earlier, I have zero homosexual attraction to men - I am always turned on by attractive women.

So im not sure if this is a psychiatric condition or something else but I'm getting really scared. I feel like I'm close to buying a wig, breast forms, stockings, a skirt, etc. and setting up a profile on a swingers dating site. Help