Well, I had planned a long post on all my points, but...lol Pandoren nailed it perfectly.

Honestly OP, I'd say as long as you don't cross the line between fantasy and reality, don't worry so much about it. It would help if you could gradually distance yourself from it if it's something you absolutely want nothing to do with...and perhaps a sex counselor could help you understand why you feel this way. But as for the mere fantasy of it, I wouldn't be so concerned.

Sanchez, my understanding between the two is that zoophilia (-philia being the Greek suffix for love, zoo obviously being animal) denotes a necessary love for the animal, almost being like a sort of relationship-esque thing. I've heard of some people who identify as zoophiles but lack any sexual attraction toward the animal...I'm not sure if that's pertinent to the differentiation or if it's a misunderstanding of the word on their part or my own, but the key point is the love. Bestiality, on the other hand, is just sex with animals.

To be fair, I suppose if you looked only at the etymology of both words (and connotations), zoophilia doesn't necessarily have to involve bestiality. But I'm rambling at this point. Point is, there is a difference, as Pandoren noted.