And the strange thing was, he did. He had always assumed he would never understand precisely what people meant when they said something like that. In theory, yes, he grasped the attachments people formed with each other, and understood how it motivated them to behave the way they did. But he could never see himself feeling so strongly about anyone, and so that part of it had always seemed alien to him. And then he had met John. It was all very strange and illogical, and Sherlock still didn't know what to make of it sometimes.