Who's read the Great Gatsby?

Okay, so I'm writing an essay on the Great Gatsby for school, and I need help. For part of my essay I want to argue that Gatsby gives up everything and becomes someone he's not because he's so obsessed with Daisy, but this is an ytic essay so I need quotes. For some reason I can't think of any scene in the book that specifically adheres to Gatsby's obsession with Daisy, but I know we talked about it in cl. Does anyone who's read the book remember a scene like that?