Disclaimer: I do not own Sherlock or the But He Didn't poem that inspired this.
John looked at the words carved into stone. Sherlock's grave.
He remembered the day Sherlock he rented a car and John had crashed it because of the case they were working. Someone had run him off the road. He thought Sherlock would be upset that he was out all that money. He thought Sherlock would get mad. But he didn't. He just sent the bill to Mycroft.
He remembered the single day Sherlock ever cooked. John threw up everywhere. He thought Sherlock would get upset. But he didn't. He cleaned John up and made him lay down before cleaning up the rest of the mess.
He remembered forcing Sherlock to take him to the beach and it rained so hard they both nearly froze to death. He thought Sherlock would say he didn't want to go in the first place. But he didn't. He got them a cab and when they got home he cuddled with John under the blanket until they'd both stopped shivering.
He remembered the time he pretended to flirt with Greg so Sherlock would be jealous. And Sherlock was very jealous. And John thought Sherlock would leave him. But he didn't. He just made John promise never to talk to another person again.
He remembered the time Mycroft forced them to go to a fancy ball. And John didn't put any clothes out for Sherlock so the dolt wore a blanket over his pajamas. John thought Sherlock would get embarrassed. But he didn't. They danced all night and had an amazing time, laughing, and taking turns wearing the blanket.
There were lots of things Sherlock didn't do. He didn't buy milk when he went to the store and he didn't get mad when John needed to be alone because he had a nightmare. He didn't stop loving John, ever. No matter what. He put up with John through everything. Loved him, protected him, and was John's best friend.
And all of these things, John wanted to make up to Sherlock. He wanted to be the same for Sherlock as Sherlock had been for him. Protective and loving and wonderful. He was going to do all these things; he had all these plans to share with Sherlock when he came back to 221B. When he came back from St. Bartholomew's Hospital. But he didn't.
John sat in front of the gravestone, staring at the unyielding blackness of the rock into which was cared Sherlock's name. His eyes slid shut, not being able to bear the sight for another second. John had begged Sherlock for one more miracle. He begged Sherlock to stop being dead, to show up with that stupid coat and his perfect blue scarf and to grab his hand and drag him off on their next great adventure. But he didn't.