Well, originally this story was just a one-shot, but then the plot bunnies hit me, so here is Sherlock's PoV.
Thanks to Lidil and mooray for reviewing the first part!
He is very active for a man who was supposed to be dead. In fact, he is, without a doubt, the most active dead person, except from Irene Adler. They text each other a couple of times, sharing their 'Everybody Thinks I'm Dead' stories.
He got bored very quick. He hated being stuck in the small room, and after the first time he had shot at the walls, Molly had taken the gun and thrown it away. He didn't have any cigarettes and he couldn't update his blog. All of his favourite activities had been taken away from him. Which was why he started pacing the floor often.
Finally, after three months, he got to go outside. He walked around in the shadows of London, letting the Homeless Network know he was still there. Not many of them seemed surprised. He asked them to bring him news of anything suspicious, especially around Baker Street. He still wasn't that Moriarty was truly gone, and if he was right, he would make sure that he would not get to John or Mrs. Hudson.
After six months he started following Lestrade. Just for fun, to see if he could do it without being noticed. He saw him solving his cases, much, much slower than when he had been around. Donovan and Anderson were still sneaking around and he couldn't help but snapping a couple of pictures. When he returned it would be great blackmail. Who knew that Anderson wore dinosaur boxers?
Almost a year had passed before he watched John. He had started to limp a little again, there were bags under his eyes. All in all he looked like hell, or rather a man who had been through hell and survived. He tried to squash the guilt inside him. He had done this, to save him, to make sure he was going to be all right. However, the justification didn't seem to work as he watched his friend.
He stands outside in the middle of the night as his friend all but runs out. He follows him to the nearest pub and watch as he gets more and more drunk. John used to bemore of a happy drunk, but that has changed. Now he is a gloomy and aggresive drunk, lashing out at every person who gets too close to him, whether they're just concerned by his appearance or they're completely hammered. Usually, he gets too drunk to stagger home, so Sherlock calls a cab for him, telling the bartender to take care of John before he leaves.
Those days are the worst.
He stands in hiding watching as John goes to the same three places over and over and over again. The hopital where he had "died", the pub and the grave with his name on it.
At the grave he always asks for the same things, like the first time he had seen him. Don't be dead. Just for me, Sherlock. Stop this, just stop this act. You cannot be dead, please come back. I'm alone again. Please...
But he can't. Not yet, no matter how much he wants to. No matter how much John is hurting, it's better than being dead. It can only be better. He should know.
He keeps watching, never really leaving. And at the end of every day, he asks himself 'Why not?'
He's running out of answers.