Personally, I am straight. Not even bi-curious. Not even 0.0001% Homoloveual in any way, shape, or form, but I am here to express my opinions about it.
I personally think that you turn the way you are, whether it's heteroloveual, homoloveual, or biloveual, through what happens early in your childhood such as events or how you were raised, whether your family was missing a father or mother figure, no sisters, too many sisters, no brothers, etc. And it influenced you as you grew up.
But that's just my opinion. Lets take a person I know, that I had met through my ex girlfriend. He was gay and open about it, and even said that his whole family was male. It was his father, two brothers, and him. His mother was divorced and left to another state or something. Growing up, he was obviously around a lot of testosterone. It kind of makes sense, but once again, doesn't in all cases.
As for Young "Love", I do not believe it. I, being 14, have thought I loved past girlfriends and been with them for up to years even. But I mean all things come to an end, and things were hard to get over, but I could never see myself finding a freshman lover and marry them. You don't quite understand the full effect of love until you get much older.
EDIT: As for love, I think 15 or 16 is the age to start. I already had love once, and honestly it was greatand tight(:, but it's one of those things that you could really hold off by masturbating. Like for real.