You know I love you with all my heart, but sweetie, you're an asshole. I've lost count of all the times you've lied to me, been mean to me, and just plain ignored me.
Sweetie, if you don't want me to interact with you, just tell me so, okay? Ignoring someone is quite childish.
So is not wanting to tell someone who your girlfriend is.
And I don't know if you've noticed darling, but she looks exactly like me. Only thinner. That's sort of disturbing, sweetheart. (Oh, and do make sure she eats enough, all right? Anorexia is not a pretty thing.)
So you're "trying to be my friend", are you honey? Try harder. Even acknowledging my existence would be nice. I mean, I know your shiny new "Goth Barbie" needs attention, but saying "hello" only takes two seconds, if you do it slowly.
Also, "everything you did was for my own good"? Honey, I am not a two-year-old. In fact, I am three years your senior. Treat me accordingly, okay sweetie? Thanks!
Now, I hope you and your new plaything become very happy. I hope you'll treat her better than you've treated me.
And sweetie? Grow up, okay?
All my love,
(Keep in mind that I wrote this in anger. I'm sorry if it hurts you, but I know it'll never hurt you as much as you've hurt me.)