“The reactions that you’re seeing are classic in terms of people not believing that bisexuality really exists, feeling that it’s a transitional stage or a form of being in the closet,” Lisa Diamond, a professor at the University of Utah who studies sexual orientation, told The New York Times.
Female bisexuality is more often accepted, not only because it has been identified as more fluid than men's, but also because pop culture has popularized — even fetishized — female same-sex experiences (think songs like "I Kissed a Girl," the Britney Spears and Madonna kiss, and Orange Is the New Black).
Male bisexuality, however, can carry more of a stigma, especially from the gay community, where some see it as a precursor to coming out entirely — at one point, science even validated this theory. And, though a well-publicized study conducted at Northwestern University did question the "reality" of male bisexuality as an orientation, a 2011 follow-up found the opposite. By studying only men who had seriously dated both men and women (as opposed to men who simply self-identified as bisexual), they concluded what we already knew — namely, that male bisexuality is in fact a real thing.
In terms of accepting and understanding bisexuality, it could be a generational thing. Some younger people have even adopted a sort of blasé attitude about defining (or rather, not defining) sexuality in regard to LGBTQ labeling at all.
“Among the younger generation, I’ve seen much more openness about bisexuality in both men and women, and often a rejection of all labels,” Dr. Diamond told The New York Times. “They’re more open to the idea that, ‘Hey, sexuality is complicated, and as long as I know who I want to sleep with it doesn’t matter what I call myself.’”
It's important to point out that physical attraction or stimulation is only one part of sexual orientation. Advocates say that emotional intimacy simply cannot be overlooked. Noted celebrity bisexuals, including Tom Daley, Maria Bello, and Cynthia Nixon, have all spoken about their love for a single person and relationship, and most celebs (Nixon explicitly) haven't even embraced the term bisexual. Because, ultimately, accepting and using the term, as well as seeing positive examples of bisexuals in the media, will work to stop intolerance and, hopefully, shed the word of its negativity. (The New York Times)