Song of the Stones

WARNING EXTREMELY SAD AU CONTENT. In which, John goes insane from grief after the R-fall, and Season 3 is actually an illusion he creates in his "Mind Asylum" a version of Sherlock's own, that he created to protect himself from uselessness, with insanity. In which Sherlock didn't survive after all, Mary was dead from the beginning, and Molly saves John's life.*Spoilers for S3*