I come to think there are various types of gayness- Gary Cooper may be one type- I still don't believe he was one. But there are some people like Robert said before that are "perez hilton × 10", they can never be closeted. Take for example Liberace, who tried to stay in the closet back in the 1950s and 60s, and he even successfully sued someone for slander, for calling him what he was. Nevertheless he was way too gay to hide it.
In some cases this is really a mental/physical syndrome, not only affecting the sexual preference, but encompassing the demeanor, thought patterns, the speech.