The song “Cleaning Out My Closet” is Marshal Mathers pouring his heart out. He is getting everything off of his chest and is settling everything he can with his mom.
Eminem’s mother abused him and used him in more ways than one and so much so that he can’t forgive her because he's tired of having to deal with her problems. He loves his brother so much and he is waiting for when he actually discovers what their mom is all about drugs and alcohol. She is just a junkie that only cares about getting her fix, but the whole time she has made them think it was about them. At one point, Eminem raps about his mother having Munchausen Syndrome, which is a condition where someone fakes illness to get attention. In this case, Eminem accuses him mom of keeping him sick for this purpose. Everything Eminem discovers about his mom, breaks his heart, even though he plays it off as it doesn’t matter. And everything she does eats away at him, but it’s his job to act like everything’s okay and to apologize like nothing’s wrong, he is saying those days are over.
And about Hailie, whom he mentions in mostly all of his songs, Marshall loves her very much and he doesn't understand how his dad could have left him; especially when he looks at Hailie and sees how much she means to him and he could never leave her even if he does hate Kim, the mother of his children.
This is a powerful song because he talks about the downs of his life and what he went through as a son, brother, nephew and father. He is trying to "clean out his closet", or "get things off of his chest” and get over the things that his mom did to him that hurt him so much but he just can't seem to do it because of how badly it hurt him on the inside, which is why Hailie will never meet Marshall’s mother because he doesn't want Hailie to get hurt and he wants to get back at his mother.
This song fully shows Eminem’s ability to write and rap. He