Three years. Three years since John had been happy. Three years since Sherlock had died. Everyday was hard; he didn't know how much longer he could go on like this. Even the most trivial thing upset him. He was done crying. He was done not feeling. This was what brought John to the roof of Saint Bart's.
He was standing there, in the same place that Sherlock had, looking down at the cars and people passing by. He didn't know any of them and they didn't know him. There were few people left who really knew him; Sherlock and Harry were dead. He didn't talk to Lestrade or Molly anymore. Mrs Hudson was never quite as happy after Sherlock died. There was nothing left for him.
John looked over to where he had been standing when Sherlock had jumped. He could feel the sharp twist in his chest that he usually felt when he thought about seeing his best friend jump. He sighed and looked down at his feet to see the message he had spray painted there. I believe in Sherlock it read.
He took a deep breath and told himself that he'd be able to meet Sherlock again; hear his voice and know it wasn't just in his head. Closing his eyes, John spread his arms. As he fell forward, he thought he heard Sherlock's voice shout his name. He dismissed it, and soon the ground took away his thoughts with a sickening crunch.
On top of the roof stood Sherlock, looking down at John's crumpled body. The consulting detective felt as though his heart was on the ground with his only friend.
He had been gone too long.