While insightful for the condition of being born into sin, it doesn't preclude the fact. The serial killer probably has a similar story. Before you take that for me throwing you into the lot with serial killers based on your sexual preference, try to realize sin is just sin, I'm not isolating yours in particular or making a statement about you personally. Hetero men looking at pictures of women is directly addressed by Christ (Matthew 5:28), and that is a sin as well, whether they realized it at the time or not. Despite their age...
It only means the condition of sin is real and we're all fallen to it. Just because you didn't recognize it as sin, doesn't mean anything. In America we have strict liability laws, for which you can be prosecuted regardless of your knowledge of them or not. Your understanding of it isn't a requisite. In fact, the enemy would prefer you not realize it.
There's good news, though. You don't have to die in that sin. Nor did I have to die to my lust of looking at women and desiring them, when they weren't my wife. Nor does anyone have to die to their sin. Heck, even Jeffry Dahmer avoided the penalty of death, if the stories are true... only God knows for sure.
Back to my assessment about it being a spiritual condition rooted in pride and what not.... You said you learned it was a sin later on, so you know? But, have you turned from it? If so, great. But if not, how come? That's what I was talking about, if that be the case.