How did Kakashi get his Mangekyou Sharingan?
Appearantly, The Mangekyō Sharingan is acquired through the death of the person closest to the Sharingan user. To expedite this occurrence, Uchiha throughout history have killed their closest friends in order to meet this criteria. To obtain the Mangekyō Sharingan, one must feel the emotion of losing a friend or family, as merely killing them or watching them die will not activate it.
I understand Kakashi lost Obito and that, but still then he didn't have the Mangekyou I'm guessing like sasuke when his whole clan got wiped out, his sharingan wasn't developed enough.
But now he has got the Mangekyou without anyone close to him dying (because he said to sasuke 'before' he developed the Mangekyou that "all people close to him are already dead")
So... How 'did' Kakashi get his Mangekyou Sharingan?