This is based off of fan artwork that I came across on tumblr. The link is post/16540437575/this-time-mrs-hudson-didnt-blame- him. Essentially, after the fall, John 'edits' the smiley face on the wall. I'd advise you to look at the artwork as it's pretty amazing.

Sherlock sat in John's chair, deep within his mind palace. He was disturbed, not that he would admit it, something was ...different... about the flat. It was obvious to his keen intellect that John hadn't moved anything thing since the fall, judging by the layer of dust present, he hadn't allowed Mrs. Hudson to do so either. He stood up from the chair and began to pace. What was different? Though his face was outwardly calm, his mind was racing, deductions flying at a mile a minute. He was so close, he just couldn't put his finger on what had changed. If only John was here... John, the man Sherlock had "died" to save, the man for whom he had spent the last three years pining while he hunted down the last of Moriarty's web. John, who would be home from his shift at the surgery in about half an hour, depending on whether or not he got a cab.

Sherlock froze, his mind singling out the anomaly in the flat. John had always been Sherlock's "conductor of light" and now it seemed that just being in the same room that John had been in had the same effect. He filed that bit of information away for a later time; right now he focused all of his considerable powers of deduction on the smiley face on the wall, and John's addition to it. He frowned, pondering the significance of the addition. When he fell, Sherlock had known that John would grieve for him, but this suggested something else entirely. Did John have feelings for me?

Of course, while they were living together, Sherlock had seen the signs. On several occasions, Sherlock's knowledge of body language had led him to suspect John had feelings for him, but given the doctor's adamant insistence that "he was not gay!" and Sherlock's admitted lack of expertise in "sentiment", he had chalked it up data misinterpretation. During the three years after his fall, Sherlock had realized that he did in fact have ...feelings...for the good doctor. He knew that John would never reciprocate them, however and he forced himself analyze his observations without being distracted by sentiment. He was so deep in his thoughts that he didn't notice the footsteps on the stair case or the door to the flat opening. He was startled when he hear a weary, "Mmm, so you're back again. I thought I'd gotten past this."

Sherlock looked at John; for once in his life he was utterly confused. Back again? He took a long look at John. He had lost weight, his face thin and gaunt with deep purple smudges under his eyes. So he was having nightmares again. Using cane, psychosomatic had returned. More grey hair present as well as an intermittent tremor in the left hand. Sherlock felt guilt lance through him as he took in his friend's appearance, and he opened his mouth to convince John he was real. The only problem was that the first words out of his mouth were, "What happened to the smiley face?"

A queer look flickered across John's face as he entered the living room with a cup of tea clutched firmly in his hands. "You know full well what happened, you're a figment of my imagination after all."

"Humor me."

John sighed, running a hand through his hair. "I might as well. I've missed talking to you anyway." He sighed again. "It reminded me of you, honestly. You were the only person I knew that would shoot the wall when they were bored. After you...f-f-f...after you fell I couldn't stand the sight of it. That bloody grin was always there, mocking me, as if it was happy you were gone. I couldn't stand it smiling at me, not when you were gone. So I fixed it. I hate that bloody smile."

Slowly, with his hands up as if John was an injured animal, Sherlock approached him. "John, I'm so sorry. I'm here now, I'm real. John?" Sherlock strode to John's side, just in time to catch the mug that fell from nerveless fingers. He set the mug down on the coffee table, turning back to John just in time to catch the fist hurtling towards him with his face. "Ouch" was all the detective had time to say before his air supply was cut off in a crushing hug. Despite the weight he had lost, John still had a fair amount of strength.

"Why?" John's voice was muffled by the fact that he was sobbing into Sherlock's shirt. "Three bloody years...oh god, three bloody years. I came so close to k...I stood on the roof of St. Barts. Why? Sherlock, oh god, you're here, you're actually here."

Sherlock felt his heart shatter at John's confession. Mycroft had never told him that things were this bad. If he had known. "I'm so sorry, John. I had to do it. Moriarty had snipers waiting to kill Lestrade, Mrs. Hudson, and you and I couldn't allow that to happen. Not to you. Please forgive me. If there had been a way for you to know... I had to take out Moriarty's entire network before you could be safe.

"Why couldn't you just tell me? I was a soldier, I could have handled it."

"No. It was too dangerous. The thought of you in danger, of you dying is more than I could bear. I had to be certain you would be safe. I've come to the conclusion that caring is an advantage. Love seems to be a powerful motivator, and I...um...I'm...I have come to the conclusion that I love you, John." Sherlock could feel the way that John had tensed as he spoke, and he mentally braced himself for John's inevitable rejection. When it didn't come, Sherlock looked down to see John's beaming face.

Before he knew what was going on, Sherlock found himself being kissed by John Watson. When the kiss ended John buried his face in Sherlock's shirt again, mumbling as he did so, "I love you too, you great big git. Don't you ever leave me again. Hmm?"

Instead of answering his blogger, Sherlock wrapped his arms around him and pulled him closer before resting his chin on top of John's head. He wasn't sure how long they stood there like that, just holding each other, but finally he couldn't resist asking the question that had been nagging him. "John?"

"Hmmm?"

"Why do you get to shoot the walls without making Mrs. Hudson mad, but I don't?"