Knew Enough To Know Nothing At All Lyrics

Lyric discussion by WishYouWereHere 

Cover art for Knew Enough To Know Nothing At All lyrics by Pete Yorn

I heard this song for the first time today and I really loved it...the meaning was kind of vague to me- it seems like there was a guy and he fell in love with a younger girl, and he just kept waiting for...she clearly moved on and never cared for him, and though he knows he's wasted so much time he just can't let her (or his conscious naivety) go?