The Soldier's Husband

1. "Married To My Work"

Right from the moment Mike took him to meet Sherlock, John knew he was in love.
He'd never been in love before, and he'd certainly never thought he was gay. But seeing Sherlock there, with his hair and his face and his cheekbones, John had known that he was 100% in love.
When Mike suggested they move in together, John was over the moon. Seeing this... Extraordinary... Man every day was going to be the best thing in the world.
The next morning, John had gone to 221B Baker Street and met Mrs Hudson, who was "not the landlady". She'd treated John like he was Sherlock's boyfriend, and John- well, he'd wished it was true.
"I've got two rooms," she said. "If you'll be needing two rooms, that is."
"Of course we'll be needing two rooms," Sherlock said, without even looking at John. John's heart sank. It was clear Sherlock didn't feel the same way. Maybe... Maybe over time?
Sherlock did like to talk to John, though. He treated him as a friend- as his only friend, his best friend. Still, John remembered the words Sherlock had said to him- "John, I'm flattered by your interest, but I consider myself married to my work." Every time John fell in love with Sherlock again, he remembered those words and forced himself to move on. He even dated other girls, even though he didn't have any interest in them.
And then Sherlock "died".

Those were the worst two years of John's life. He'd been desperate for Sherlock to come back- he didn't know how he was going to live without him by his side. He didn't know how he would be able to cope. He missed Sherlock every day- it was then that he realised that the other girls had never mattered. He had loved Sherlock more than he'd loved all of them combined. And now he could never tell Sherlock how he felt.
He decided to move on, after about six months. He tried dating another man, but he realised that every man would remind him of Sherlock. Instead, he found a woman who was almost the complete opposite of Sherlock Holmes- Mary.
He spent forever trying to fall in love, and finally he did. In fact, he proposed to her. The day he'd planned to propose to her was the best- and worst- day of his life.
Best because he had Sherlock back. Sherlock, the man he loved more than anyone else in the world. His best friend.
Worst because he had Mary now. Mary, the woman he loved. He didn't want to leave her.

So he stayed with Mary, not returning to live with Sherlock- he thought it could convince him to leave Mary. He did love Mary- he married her, even, and then Sherlock told them she was pregnant. John saw sadness in Sherlock's eyes when he told them- was he sad to lose his best friend, or was he maybe feeling what John felt for him?
Then Sherlock went into that goddamn drug-induced mind palace. John had thought he was going to lose Sherlock then- he'd thought he was going to die. So that night, when Mary was asleep, he'd snuck out and run to 221B Baker Street.
He knew that he couldn't wait any longer- he couldn't lie to himself. He loved Sherlock.