You kicked me when I was down
I do not believe it is a reference to Relapse, seeing as he was back to normal on Relapse. I think it is a reference to maybe his hiatus. People often forgot about how BIG Em was and people never really raised an eyebrow at his health issues and drug problems, as well as his depression. There was no sympathetic woes from his fans during his absence, just complaints about Encore and Re-Up.
Like said above, this could be targeted at Lil Wayne as well. When Lil Wayne said he was afraid to work with him when Em was going through such a hard time or “kicking him when he’s down”, making it seem like he might lyrically beat Eminem on a song; when usually Eminem takes over any song when he’s featured on a song with another rapper.
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