Would it not be discrimanatory to only destigmatize one form of "alternative lifestyle"? Such would be the mindset of other deviant sexual identities, like bestiality, pedophilia, polygamy, and so on. Passage for One facilitates passage for All. Destigmatization from desanctification. And then nothing is sacred. Like a cesspool, so favorable to endless varieties of harmful organisms. That is what best illustrates the opening of that forbidden door by gay activism.
These other groups have recently been inspired, empowered and emboldened by gay "rights" victories, and are copping the same playbook as the gay activists, same talking points, in their own lobbying toward legitimacy. Have a look for yourself:
http://www.gainesville.com/article/20121211/ARTICLES/121219923/1034?p=1&tc=pg -legitimizing bestiality inspired by gay activsm