Not gonna respond to your specific situation because I don’t know enough about zoophilia.

Re: should your spouse know about unconventional attraction, I think it depends on how much it affects you on a day to day basis, and how much it affects them. It was really important for my wife to know about my attraction to men. Not so much because of the attraction itself, but rather the psychological damage from it. Most of the time it has no effect on our relationship. But on occasion, if I’m depressed, or I’m withdrawing in a social situation, or I’m uncomfortable around some guy, or I tell her “listen, I’m having a really tough time, I think I need to restart therapy,” there’s an understanding and support.