Half what?

Light is half dark
  Know that?
                                               I do glow

Dark has some light
  Nothing is absolute
                                               I am human

Love has some hate
  Because no one is perfect
                                               I know you still love me

Hate includes some love
  Because you must love someone to mark them so, right?
                                               So don't pretend to hate me

All things include part of their opposites
So when I say that you are the opposite of me, yet the only one similar
Know that I mean part of you belongs with me
As a part of me belongs as your other half