I think the only death in this song is the end of a really meaningful relationship (friendship could also be included). The singer seems like they didn't apreciate the time they had with a special someone (neighbor, best friend, lover, whatnot) and now that the other party has gone (died, etc.) the interpreter is finaly realizing what he/she had. It's that age old situation: You don't know what you've got till it's gone. It does seem like the singer would apreciate the person more if they had "one more day", but one more day is just one too many for the inspiration of the song.
I think the only death in this song is the end of a really meaningful relationship (friendship could also be included). The singer seems like they didn't apreciate the time they had with a special someone (neighbor, best friend, lover, whatnot) and now that the other party has gone (died, etc.) the interpreter is finaly realizing what he/she had. It's that age old situation: You don't know what you've got till it's gone. It does seem like the singer would apreciate the person more if they had "one more day", but one more day is just one too many for the inspiration of the song.