After a couple of listens to the song i have got a bit of a view on it. When he starts talking about how he is too busy for Halie then he says he goes into the booth and says how much he loves her at the same time talking about how puts his hands on Kim, he is referring to Slim Shady (Marshal is the family man) (Eminem is the rap genius). a few bars later he says that "Shady's Rock a Bye Baby" meaning he is going away\ to sleep. So i think that Eminem might be putting to rest the drug, dark, angry side of his persona, the Slim Shady Side. And at the end it might be the Shady side of him dying, smal chance the Eminem side but not Marshal as a Rapper.
Let me know what you all think!
Bye the way I Love the track, 'even best of' worthy