I'd like to see an explanation why you believe society should cater to the recognition of certain forms of abnormal sexuality, and not others.
1. "Abnormal sexuality" is in the eye of the beholder, so no one person--or group, for that matter--should be telling any other adult what to do in the privacy of their own home with another consenting adult.
2. Homosexuality and pedophilia/bestiality are two very different things. A child or an animal cannot properly consent to sexual activity, while a reasonable adult can.
I'd like to see a response to these ideas.
#2 is an exercise in circular reasoning. If you declared homosexuality an illness rather than a wellness, or as you put it you exclude them from the pool of "reasonable adults," then you could claim that no individual could "properly" consent to homosexual activity, no more than an alcoholic can "properly" consent to having a drink. It would seem that an animal mounting a human being could reasonably construed as a willing participant. Certainly, juvenile male dogs behave in strange ways. If a child of seventeen is considered "reasonable" enough to consent to sex with a child of fifteen, then, you have to explain why he or she isn't "reasonable" enough to consent to sex with an eighteen year-old? We have laws against bestiality, not animal rape. We have law against underage sex because we have made a social decision that children are off limits. The "consent" of the child is irrelevant.
as to #1, you really have to explain why at eighteen you magically gain the ability to make "reasonable" choices that you lacked at seventeen?