When you know i cannot take anymore living without you
when you know you are the first and the last for me
when you know i am waiting for you till the death
when you know i don't wanna tell anybody 'i love you'
when you know that entire thing
why are you leaving me?
when you have given your heart to me!

Little Sunshine

http://www.poemhunter.com/poem/when-you-know-4/