Best Friends Death?

When someone close to you dies all sorts of ppl come out of the woodworks...which is nice dont get me wrong. But what do I say, or what to ppl expect me to say when they say things like 'im sorry for your loss' or 'sorry about your friend' or 'how are you?'....you know? do i say 'thanks, but no thanks i feel like i wanna curl up in the corner and die' or something like that. How do you handle that type of situation gracefully?