1)Fitting into a box is terrifying. Not fitting into a box is both exhilarating and terrifying.
A box (be it socially acceptable or not. gay/straight/gender queer) comes with convenient labels to tell society who you are and what you do, plus people can identify with other people who fit into the same boxes as they do. Not fitting into a box is exhilarating because you're not doing what society says you should do, ergo: you're not a "mindless sheep" - you're "different" "special"; however, you still have to constantly explain yourself and put up with the BS from people who don't want to or are simply incapable of understanding.
2)Humans need a box of some sort to survive. We can't be everything and anything (that usually =crazy as in not perceiving the world right), because we come with built in limitations.