David Bowie was an individual who experimented with different forms of sexuality. Although, he admitted years later to being heterosexual. Some would say that his sexuality may have been fluid. I just feel that David Bowie was who he was and that was good enough. He inspired millions and will continue to do so. Who cares about his sexuality?
David Bowie had a wife, Samalian super model Iman, with whom he began his partnership in 1990. Though he was a fashion icon and may have leaned twoard some stereotypically homosexual tendencies, I don't think it's fair to speculate that he was a secret heterosexual as opposed to a genuine out-in-the-open heterosexual. Sure, some homosexual men marry straight in order to satisfy a public image, but I think David Bowie's relationship with wife Iman was genuine. If anything, it would be fair to suggest that Bowie was a metrosexual.
David Bowie has shown to be a guy who can express himself and not care about what the public thinks. He is a legend and an icon who will be remembered for his sense of style and fashion. But just because someone is expressive doesn't mean that he is a closet homosexual.
Nobody will ever really know, but a closet heterosexual means he was hiding it and his marriage to Iman doesn't really jibe with that. Maybe he was bisexual, maybe he was married and was never openly gay because it was so hard to be open, but we can't just declare someone's choices based on rumors.