How?

Just like that small boy, I never was a man Until I saw your blue eyes cry As I held your wet cheeks in my hands I wished the world to make it go away To put that smile back the way it used to be Then you said “how can you do this to me?” At that moment all that was left of me was dead I’ve hurt the one I cared for I’d wounded you with the things I’d said All the world can’t make that go away Now we'll never do the things we used to do Then I said “how could I do this to you?”