(1) the hardest part of ending, is starting again.
(2) the hardest part of ending? … is starting again.
on (1) he’d be saying that the hard part of ending a relationship is about to begin.
on (2) he’d be saying the hard part of ending one relationship, is starting all over again on a new one.
Which one is it?! Ahhhh! I know it’s not important, but oddly enough this question popped into my head the first time i heard the song.