You felt the pain when they walked out the door
and you've been in fights
and you've been in wars
but you never felt anything like this before
why does it hurt when their leaving
You were glad when they left
it made you feel free
like a burden was lifted that buckled your knees
you didn't get on
and you didn't agree
so why does it hurt when their leaving.
Charles M. Moore
http://www.poemhunter.com/poem/why-does-it-hurt/