Dear Severus,
I have always been very fond of you; possessed of a brilliant mind and a kind heart when you try, you are a very dear friend. You are a genius in potions, and almost anything else to which you set yourself. I have always admired you, my friend.
We have shared a common 'enemy', if you will. James Potter was always little more than a prat, despite his good looks and actually decent spell work. Remember the time he used that spell on you, lifting you upside down? I have always tried to protect you from him and his antics; and you have always done the same for me. Severus, I can never thank you enough for holding me while I cried over James. He did not deserve my tears then, and all he accomplished was showing me how good a friend you really are to me.
And yet, I am about to become a terrible friend to you, Severus. Despite all the things James has put you and I through, he has stolen my heart. I feel this is nearly a betrayal of our friendship, to fall in love with the 'enemy' like this. I would never want you to feel I have abandoned you; however, this is what the fates have determined. I will always consider you my dearest friend, Severus, and I hope you can view me in the same regard in future years.
Sincerely yours,
Lily Evans
Lily,
I have always admired your courage- the courage you showed to help me and stand up to Potter and his cronies- and considered you my friend. You were ever the Griffindor coming to the defense of a friend, helping me when no one else would. Lily, you became the sun of my world, the only bright entity in the wash of night and loneliness and pain. This announcement however- it comes as a shock. You, Lily, have indeed succumbed to the enemy.
You should know that I never considered you a friend. I loved you, the one person to show me kindness, my sun. But this love I held for you and your brilliance, it will be gone from me soon. I suppose in retrospect this was to be expected, as such a thing as me could never be matched to you. Soon, however, this will be irrelevant conjecture.
Lily, you shall never hear from me again. I will forget you, forget the feelings I had misplaced in you, and go live a different life. Hogwarts is ending, the dream is disintegrating, and you have been taken from me, so there is really nothing left. I will go back to my spells, my potions, my studies that have supported me thus far.
Goodbye, Lily.
Severus Snape