See, Dean. He does know the difference, now. What you were doing, dragging him around, acting like he was a monster, punishing him for being different... That was using him. Your father asked you to protect him, not shove him out of your life.
My angle? You really aren't the brightest... It's a wonder you're still alive. You see, Dean. I'm here because it's God's will. My brother did the same thing as you did to Sam, and now, God wants us to finish it.