The room was quiet and still, the only sound Mary's soft breathing as she lay curled on the mattress beside him. John stared at the ceiling wondering what the hell was wrong with him. Tonight should have been the best night of his life. What had happened between him and Mary …

He deserved this, dammit!

Mary was everything that Sherlock was not. Warm. Caring. Open. And above all, honest. She loved him unreservedly. Even though he was far from a prize catch; pushing forty, no career to speak of, a has been who never really was, she had willingly thrown in her lot with him.

So why did he feel so bloody awful?

Why did he feel like he'd just made the biggest mistake of his life?

Why did he feel like he should scrawl a note of apology and steal, shamefaced, from their bed?

He glanced over, resisting the temptation to stroke Mary's cheek and wake her. After the ambiguity of his relationship with Sherlock; one minute casual, the next intense, finally ending without warning. After Sherlock's lies. His deceptions. His ceaseless, remorseless betrayals, all of which John had forgiven, stupidly, because for some reason he just couldn't stay angry at the man who made him feel truly alive.

Mary wanted him.

She wanted to be with him.

He knew he should feel blessed. Instead he lay there next to her feeling sickened, as if his world was on the verge of collapse and there was nothing he could, or should, do other than surrender and fall into the void along with it.

He stared back at the ceiling again for a long moment and then shook his head firmly against the pillow, a surge of anger rising to eclipse his doubt.

He had done nothing wrong.

It wasn't a sin to want something better for himself.

It wasn't a sin to find happiness with someone who loved him without compromise.

Sherlock wasn't the only one who could slam a door on his old life. What was done, was done. It was time to shake the dust of 221B Baker Street well and truly from his boots and stop looking back. He could put away his guns and let others fight the wars and hunt the bad guys, as Mary wanted him to.

Sherlock bloody Holmes could bloody well accept it.

"Brave words, Watson."

The voice floating up from John's subconscious was that of his first Sergeant Major, that grizzled lifer who never directly contradicted his decisions, but always found a way to make him second guess every little thing; from the way he tied his boots, to the time he spent reading medical journals.

John frowned, wondering what it was about three in the morning that made it so easy to argue with himself.

All right, so maybe it wasn't going to be a cake walk. Maybe Sherlock would always have some kind of hypnotic pull that would draw John to his side. Maybe he was just too much of an adrenaline junkie to give up the sort of adventuring that Sherlock's world offered.

And maybe, dammit, despite the fact that Sherlock was a stone cold arse, he was still John's closest friend and they needed one another, filling the hollow spaces in each other's psyches like no other person could.

His numerous eccentricities and failings aside, when Sherlock wasn't pretending to be dead, he was unfailingly loyal. When he wasn't lying through his teeth, he was uncompromisingly honest. Few people shared John's bemusement with the absurdity of life the way Sherlock did. And even fewer people understood John's disparate nature, embracing the soldier and the healer equally.

Sherlock's willing acceptance, his pragmatism, had helped John transition back into the civilian world by giving him a place in it. Even if that place was somewhere on its fringes. Because of Sherlock's generosity, John would always be grateful. For that reason alone, he knew he could never willingly ignore Sherlock's summons, no matter how shoddy the circumstance.

He shut his eyes and then opened them again, rolling over onto his side so that he could watch Mary sleep. She was so beautiful. So good to him. So good for him, helping him see that there were other ways that he could live his life and make a difference; ways that didn't involve staring down a gun-sight in a godforsaken hell hole or a London back alley. She made him see there was more to him than an adrenaline junkie looking for his next fix, and that there was a place for him that wasn't on the fringes of society.

"John, are you all right?" Mary asked softly. Still caught in the throes of sleep, she reached out a hand and sought to reassure him.

He smiled at her, the weight on his heart heavy, and nodded. He stroked a fingertip over her cheekbone and then scooted close enough to kiss her softly. "I'm fine, love, go back to sleep."

She took him at his word, settled against the pillow, and drifted off again.

John watched her for a long moment, vowing silently to get his head straight. He rolled over onto his back again and closed his eyes, but sleep still eluded him. He no longer felt whole. Once again he was a man divided, pulled apart by the people he loved most. He knew in his guts that he was standing on a crossroads and no matter which path he chose, for someone, heartache lay ahead.