From Andrew Sullivan's heartbreaking article:
Andrew Sullivan: Why Gay Marriage is Good for America - The Daily Beast
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"As a child, when I thought of the future, all I could see was black. I wasn’t miserable or depressed. I was a cheerful boy, as happy playing with my posse of male friends in elementary school as I was when I would occasionally take a day by myself in the woodlands that surrounded the small town I grew up in. But when I thought of the distant future, of what I would do and be as a grown-up, there was a blank. I simply didn’t know how I would live, where I would live, who I could live with. I knew one thing only: I couldn’t be like my dad. For some reason, I knew somewhere deep down that I couldn’t have a marriage like my parents.
It’s hard to convey what that feeling does to a child. In retrospect, it was a sharp, displacing wound to the psyche. At the very moment you become aware of sex and emotion, you simultaneously know that for you, there is no future coupling, no future family, no future home. In the future, I would be suddenly exiled from what I knew: my family, my friends, every household on television, every end to every romantic movie I’d ever seen. My grandmother crystallized it in classic and slightly cruel English fashion: “You’re not the marrying kind,” she said. It was one of those things that struck a chord of such pain, my pride forced me to embrace it. 'No, I’m not,' I replied. 'I like my freedom.'"
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Suicide is tragic, especially teen suicide. We can't calculate how many gay teens commit suicide and we can't calculate how many gay teens commit suicide for the reasons Sullivan describes, but we can give gay teens a reason to look forward to the future, hence the "It gets better" campaign.