The moment John Watson saw Sherlock's face, he knew his new found simplistic life was about to fall apart.

After Sherlock's death, John had mourned for months. He sat in apartment 221B, staring absently at the walls and trying to come to grips with the loss of the greatest man he had even known. Sherlock had been infuriating, and at times annoying to the point of extreme irritation, but John had clung to him and his lifestyle so desperately that he had lost himself within it. Without Sherlock Holmes, John did not know who he was supposed to be anymore. A doctor? A soldier? He couldn't remember.

After returning from the war, John had been lost. The streets of London were foreign and unfamiliar, and his guard had been raised to everything around him. The truth was, he couldn't quite turn off his soldier's instincts. He was constantly on the lookout for danger, his defences drawn against every strange face and unforeseeable circumstance.

And then came Sherlock, with his deadly life and dangerous adventures, and John had become infatuated by it. He finally had a reason to keep waking up in the morning, his soldier's instincts put to use. John had fell easily into step with Sherlock, depending on him like his own identity relied upon it. But that didn't mean John enjoyed every aspect of Sherlock's companionship.

Sherlock was larger than life, and while John sometimes enjoying drifting contently in his shadow, there were times when he felt so overwhelmed by his impertinent and illustrious counterpart. Theirs was a relationship of dependency, John needed Sherlock, who in turn never needed anyone. Sometimes John felt as though being around Sherlock somehow managed to be the most satisfying but unrewarding time of his life.

And so he dated. Obsessively. John couldn't stand being single for long periods of time. When a relationship failed, he mourned for a number of days before turning his attention on a suitably available and interested woman in his life. John Watson, who relied so heavily on his best friend to give him a purpose in life, constantly craved the dependency of another person. He needed to feel needed, and it was the one thing that Sherlock Holmes could never give him.

Sherlock's death had transformed John into a directionless man desperately clutching at the straws of his rapidly deteriorating lifestyle. Things were slipping through his fingers that Sherlock had once held together. His relationships with Mrs Hudson, Molly, Lestrade, and their other acquaintances faltered. He never called any of them, or made an effort to keep up with their lives. It was as though it wasn't just Sherlock who had passed on, it was the pieces of John's life that Sherlock had stitched together. His friends, his home, his job and his stability had all collapsed around him, and picking up the pieces was something that John could simply not do on his own.

And then he met her.

Mary.

Even thinking her name gave John a rush of emotions he could barely contain. She was everything he needed in the absence of Sherlock. She was kind to him, and made him feel as though he was, as an individual and not just Sherlock's companion, important. She made him feel as though she needed him, and together they were able to piece together the fragments of John's life, and rebuild them to create a beautiful mosaic without any of the darkness of John's past with Sherlock interwoven in the pieces.

What they had was nothing like John's previous life with Sherlock, which was a constant battle of indulging his darker urges and following a man blindly out of admiration. John's life with Mary consisted of a warm house, a warm body in his bed next to him, a simple job, and the mutual dependency of a couple in love. John didn't realise how happy he could be out of Sherlock's influence, but he was the happiest he had been in over two years.

And then he returned.

And the life he had built with Mary was like a house of cards in the wind; a light enough push and it would all fall apart.

His lovingly stitched together mosaic strained as his eyes scanned the face of the man who should have been long dead. John had held that man as he died, buried him, grieved him, and then he had moved on with his life. But seeing Sherlock's face ignited a part of John that he thought had been buried with his friend. A hunger for adventure and mystery and danger.

And just like that John's mosaic changed again. Sherlock's influence had woven its way once more into the very base of John's life, and his need to prove himself to the man whose every action was committed with the intent of tearing apart another human being flared up again. John could feel the eyes of his beautiful girlfriend watching him in confusion as John had pulled himself to his feet.

John felt a tidal wave of emotion so intense that grasping onto just one emotion seemed impossible. So he took hold of the first one, the first emotion he could recall feeling the moment he first recognised those perceptive blue eyes under that mane of shaggy dark hair.

He threw himself at Sherlock in anger, knocking him to the ground with a loud thud followed by the shouts of other patrons in the restaurant. John had blocked them out, his soldier's instincts rekindled in the wake of Sherlock's presence, his hands gripping themselves tightly around Sherlock's throat.

John was angry that Sherlock had returned, and shattered the peaceful life he was leading, but it was more than that. John was angry Sherlock had returned on the basis that everything he had built for himself was expected to be simply put aside to usher Sherlock and his infectious lifestyle back in. John was angry that Sherlock had the audacity to try and surprise him rather than just simply picking up a bloody telephone or even sending a text.

And John was angry that Sherlock had been out there for two years.

Out there in the world, in the face of danger, risking his life for the sake of England.

Without letting John follow.

John knew that given a choice between a domestic life with Mary and the thrill of following Sherlock's coattails, his choice would be immediate.

It was also anger at himself that made John's fist collide with the side of Sherlock's face, anger that this arrogant man had such a hold on him.

But John knew as he brought his fist back to Sherlock's face, that he could fight back his darker side just as he was fighting the embodiment of it. He would choose Mary. He wanted to choose Mary.

If he could only remove his dependency for Sherlock Holmes from his mosaic of fragile pieces, then John knew he would be happy. Mary made him happy.

But being around Sherlock had always made him feel more alive.