I don't understand

I don't understand why you left
i wish i knew the reason
every time i call you up
you never wanna talk

i don't understand you anymore
it's like we've drifted apart
i ask you questions you use to answer
but now you just won't talk

i don't understand what I've done
i never meant to hurt you
i broke your heart
in two thousand pieces
i wish i never did that

i don't understand why you hate me
i wished you never would
I'll always love you in a way
but sometimes hate you too.

i don't understand why you left
i wish i knew the reason
every time i call you up
you never wanna talk

! I DON"T UNDERSTAND!