When I was a teenager, and even in my twenties, I tried to convince myself that I was straight. Later, in my mid to late twenties, I did my damndest to convince myself that I was bisexual. Somehow, I came to my senses in my thirties: I cut the crap, and accepted that I REALLY like men--everything about men: cocks (obviously), faces (esp. eyes and smiles), hands, feet, hairy bodies, the sounds of a male voice, the way men move, the shape of their butts, and so on and so forth.
Here's what kept me from embracing this reality when I was younger: I had bought into the notion that as long as I behaved like the typical "straight guy" in just about every situation (naturally, not pretentiously), even though I fantasized about (and was having sex with) men, I couldn't possibly be a true homosexual. In other words, I wanted to correlate certain so-called masculine traits I exhibited with being heterosexual or bisexual. I was fucking around with guys, but I wasn't effeminate, so I refused to classify myself as "homosexual."
Now that seems ridiculous to me. And I believe that until our society fully recognizes and accepts that your average, everyday guy-next-door might actually be attracted to other men, regardless of how he looks or behaves, a sizeable percentage of homosexual men will continue to hide their true sexuality and live two lives--and many will remain fully repressed behind a facade of heterosexuality simply because they don't want to feel rejected by those who make up the majority (and there are still so many who shun the notion of homosexuality--just think about the place where you work, or the couples you see at the park or beach or mall).
How unfortunate, really. And how unnecessary.