He's waiting for his life to begin, as he envisions it, but he doesn't fit in with the social norms, and he doesn't want to explain himself, and doesn't want to hear your explanation for his existence or how he should feel.
He feels as if he has seen or experienced life in a billion seasons and that's what makes him different and this creates this barrier between him and others.
Interpretation:
He's waiting for his life to begin, as he envisions it, but he doesn't fit in with the social norms, and he doesn't want to explain himself, and doesn't want to hear your explanation for his existence or how he should feel.
He feels as if he has seen or experienced life in a billion seasons and that's what makes him different and this creates this barrier between him and others.
Just what I think.