In. Out. In. Out.
That's all John could do anymore. Focus on his breathing. If he didn't concentrate, he forgot to do it. He'd lost all will power since Sherlock had… moved on. As long as he kept breathing, life would go on.
In. Out. In. Out. In.
John sometimes wished he would die. Just pass away in his sleep. Because Sherlock had been everything to him and now that had been ripped from his life without reason and without warning.
In. Out. In. Out.
Sometimes, when John had a panic attack, breathing wasn't enough. He'd place his fingers against his neck and count his heartbeats.
1. 2. 3. 4. 5.
John had an heart rate of an average 76.6 beats per minute.

Since Sherlock had… left, everything John did became incredibly scientific; calculated.
He'd turn the kettle on.
In. Out. In. Out. In. Out.
1800 watts heated water to 100*C.

In. Out.
He'd go out for a walk. A car would go past.
Combustion engine. Catalytic Converter.
A bird would chirp in a tree.
Sparrow. Song wavelength of approximately 5000Hz.

In. Out. In. Out. In.
Yellow Irises. Absorb red and green light. Sherlock's favourite spring flower.
Too soon.
InOutInOutInOutInOutInOut
1. 2. 3. 4. 5. 6. 7. 8.
In. Out. In. Out.
Calm. Deep Breaths.
When this sort of thing happened, John would return home and curl up on Sherlock's bed, enveloping himself in Sherlock's sheets, his clothes, anything that would remind him of the man who was… absent.
In… Out… In… Out… In… Out.
John's breathing would slow down to almost half it's normal speed, as though savoring Sherlock's smell. He'd sometimes forget how long he lay there for. Mrs Hudson would find him curled up in a ball, whispering the count of his heart.
945. 946. 947. 948.
In. Out. In. Out. In. Out.
The record was 3275 before he was discovered.

Eventually, John was able to go back to work. It took three months for Sarah to stop asking him on dates. It only took one for John to run out of excuses.
Ear infection.
In. Out. In. Out.
Chesty cough.
In. Out. In. Out. In. Out.
Some kid trying to get out of school. Clearly not ill.
In. Out.
Pack up. Go home. Wrap up in Sherlock's blanket.
In… Out… In… Out… In…
Fall asleep on sofa. Wake up. Smell Sherlock. Realise Sherlock is… missing.

1. 2. 3. 4. 5. 6. 7. 8.
Go upstairs. Sleep in Sherlock's bed.
Repeat.

John carried on like this for days.
Months.
Years.
In. Out. In. Out. In. Out.

As time went by, it became less and less noticeable to others. Mrs Hudson no longer found him crying in Sherlock's room. But that's because he did it when she was asleep.
In. Out. In. Out. In. Out.
20143. 20144. 20145. 20146.

Noone was there to stop him. Noone came to comfort him. The longer Sherlock's… absence dragged on, the less his smell lingered on his things. It took John longer to calm down each time. He was losing Sherlock. He didn't want to lose him. God.
InOutInOutInOutInOutInOutInOutInOutInOut

John would sleep less and less each week. He found out after a while how easy it was to stay up, like Sherlock had. Days on end without sleep.
John would do that a lot.

Eventually, Sherlock's smell dissipated altogether. John stopped having panic attacks. But every single night he would fall asleep with his fingers on his pulse, in Sherlock's bed. Just to remind himself to keep breathing. For Sherlock.
In. Out. In. Out. In. Out.
381. 382. 383. 3..8..4…..

1… 2... 3.
John awakes groggily. He keeps his eyes closed and concentrates on the pulse under his fingers.
4. 5. 6.
In. Out. In. Out. In. Ou—
John's mind suddenly snaps into place. There is a pulse under his fingers. It is not his own.
His eyes fly open.
A mop of curly black hair is on the pillow next to him.
14. 15. 16.
In.