I am gay but I can only get hard off girls

I just can't get hard off guys. I can tell if they are attractive but, even when i think of guys my boner goes away. I know I am gay though. How come I can get hard off the /s/ board but not the gay porn on /b/?

Way to bumb a 900 year old thread... Non faggot. Seriously your clearly not gay if you get a hard on of girls.. Go shuv ya tiny pee pee in a girls boom boom.