I'm sorry, John. Truly I am. I'm sorry for everything. I'm sorry for spoiling your relationships—although really, none of them were likely to last very long anyway—I'm sorry for the nonchalant way I usually treated you, I'm sorry for getting you involved in so many horrible ordeals. I'm sorry I've made you sad, and I'm sorry I had to lie to you. But most of all, I'm sorry I ever doubted you. I'm so, so sorry that I let myself lose trust in you for even a moment. I never should have accused you of believing those people, of believing all those things they were saying. I was just afraid. Terrified, actually, that I was going to lose you, the only friend I'd ever had.

These are just excuses. None of them can make up for what I've put you through. I just thought you should know. I'm so, so sorry about everything. I let you down. I told you before not to make people into heroes, because they don't exist and even if they did, I wouldn't be one of them. I thought that would be the end of it, but I guess I was wrong. Why me? Why, out of all the people in the world, would you pull me out of the crowd as your hero? You could have someone so much better—someone kinder, warmer. There are so many out there better than I, so why don't you look at them, even now? How could you have so much faith in me? I don't understand. After everything that happened, after Moriarty and the Woman, you still just refuse to believe that I ever lied.

Molly's been taking care of you, just like I asked. I've seen her come to the flat, and I've seen you let her in, but every time you look more haggard than the last. You're scaring me, John. I'd never felt fear before I met you, and now it's all I feel. You've lost weight. Are you back to not eating? I know your limp's come back, even though you know bloody well that the injury was all in your head the entire time. Why would you let someone like me affect you so much?

I miss you, John. So, so much. I don't know how to respond, because I've never felt this way before. I don't understand it, but I just want to be back in 221B with you. I want to be living with you again, to have you yelling at me for keeping my experiments in the fridge—honestly, where else could I keep them?—and just…just to have you as my best friend again.

I'm so, so sorry, John Watson. It's my fault you're hurting now, but I swear, it won't be forever. I'll come back, and when I do, I'll never leave again. I don't think I could survive this separation a second time. I just have one request: don't hit me too hard, please.