Because there's not an asexual in the world who hasn't thought this or felt this. Even those most content and secure with themselves have undergone long periods of doubt, denial, confusion, and self-reflection.
I think we often feel we don't have the right to complain or say anything though, since we're not really targets. We don't get hate-groups or slurs (usually). We don't get the violence or harassment. People don't even know we exist. Or, worse yet, they deny it. Say that we're confused, say that we're in denial, or defective. When we are told that we are something we're not, denied acknowledgment, or completely unheard of; it makes us feel very alone. Very secluded. The rest of the world gets it, so why don't we? Or, why can't we? Literally, everywhere around us we're surrounded by "what is normal". Most music you here is about relationship and sex, most advertisements you see are targeting sex appeal, and most movies, books, and tv shows involve some sort of romantic plot/subplot. We are drowning in a world that we don't feel like we belong in. Compounding the problem is that because we're so uncommon (the most common statistic being 1%) we often aren't even aware that others like us are out there. Finding another asexual is quite rare; many asexuals aren't even aware of themselves.
I've been fortunate enough to have several online comrades who happen to be asexuals, but all though my adolescence I went through life thinking I was the only one like me. But, again, I think that is quite normal for asexuals. And it's really tweaking me out that the spell check isn't recognizing 'asexuals' as a word because it doesn't recognize it as a noun...
So all in all a pretty awful poem that's more of a rambling with line indents. But, then again, I guess that 87% of most poetry anyway!