John,
There are plenty of times that I have wanted to write you, to say these things to you, but we are both aware of my inadequacies in the department of sentimental emotion.
I did not have much before you came along. My only true friend - who I was unaware could be considered as such at the time - was Molly Hooper, who I am forever greatly indebted for the things she has provided and taught me. She has made me view reason and forced me to see and understand things that I was previously incapable of. These things that I speak of are many, but most important of all, is you.
To say that you have affected my life would be a gross understatement, for without you by my side I fear that I could have, on many occasions, succumbed to many downfalls. My addictionswere many, my inability to fully understand the most basic of human emotions was significant, and my need for companionship in a good friend was unknown.
The hurt in your eyes upon my return to London would have gone unnoticed had you not taught me to understand it, and while I might have given the persona at the time of an uncaring, unwitting imbecile, I fully understood the results of my actions. It was the night of my return, walking away from the diner with blood still pouring from my well-deserved injuries that I stood in the same place you stood when you made one request: don't be dead. I heard you, John, the words resonated within me and provided me fuel to continue on my mission to return to London, to the life and companions I had grown accustomed to.
What you must understand is that two years ago I was laid to rest, not as a human form who had thrown himself off the roof of a hospital, but as the man who existed before the sudden interruption of an army doctor in need of a flat, and a new sense of adventure. When I returned, when I understood the hurt in your eyes, it was the birth of a new person. I protected you before, from the snipers, from Moriarty, but I developed a new sense of need to make sure no harm, physical or emotional, befall you, and it is with that fire that I did the things that I did that have brought me here.
To say that we will see each other again will only inflict more pain upon you with a false sense of hope, for when I boarded the plane to my new assignment I knew my fate had been sealed. These are all the things I wanted to say but couldn't, for fear of the emotion I might see in your eyes, emotion that I would not have understood had it not been for a man with the strength to put up with someone as atrocious as the man who put chemicals in his food, who constantly ridiculed the ability of your brain to function at a level beyond that of a mediocre human, and a man who lacked the mental capacity to understand that this is what he had been searching for in all the years before he met you.
I hope your adventurous spirit has calmed since the birth of your child, safetys have been put in place to assure that you and your family will always be protected. I will no longer be capable of holding that position, though I fear it is I who has resulted in the need of the position in the first place.
It is in closing that I wish upon you, Mary, and your growing family the greatest of happiness without the fear of danger. For I can leave this world knowing you are well protected and taken care of. I welcome you to reflect back on the adventures that we shared together, but ask that you keep them just a memory, for the life you now lead deserves to be a quiet one. It is with this that I must bid you goodbye, dear friend, and wish upon you the highest of health and happiness, for your years remaining are many.
-SH