Some days were good days. Sherlock would bump into John on the street and they would end up going for a coffee, or for a stroll in the park. Sometimes Sherlock would deduce someone for him, and he would be able to coax that smile out if John— the one reserved only for him.
Other days, Sherlock would concoct a reason to be one of John’s patients at the hospital, where the staff knew of John’s condition and made sure he still had work (and never knew what day it was). He tried not to notice the pitying stares from the nurses as he came in with another case of “dehydration.” It was worth it, because he was able to see John in his element, as a doctor, a healer. Sometimes, he would only watch from afar, and never talk to him at all.
The best days were the ones in which he would be able to get John to go with him to Angelo’s, or even on a case, in a strange repeat of their first day together— before Sherlock had known about his short-term memory loss. Those were the days he lived for, because he saw a glimpse of the man who had looked at him with awe on the first day they’d met, the man who shot down a cabbie in defense of him. He learned exactly how to act, how to touch, what to say, in order for his John to breathe into life. Sometimes those days even led to stolen kisses outside the restaurant, or just gentle caresses and touches before Sherlock sent him back to his own flat.
Then there were the bad days. After a few months, Sherlock was able to notice them right away, but he never stopped trying to reverse them. The days when John saw the newspaper and realized what year it was, or he woke up with complete dementia, or— by far the worst— when he would completely brush Sherlock off.
Mycroft and even Lestrade constantly tried to get him to leave John be. They probably could tell that he was at his breaking point more than once. He didn’t care.
He would spend the rest of his life this way if he had to. Being with John, even like this, was better than not at all.