Former Guns 'N' Roses manager Doug Goldstein 'fessed up in a Rolling Stone Brazil interview just why Axl Rose and Slash haven't been friends for nearly 20 years: Michael Jackson. Apparently, it all started when Slash performed with Michael Jackson during a 1991 concert. 

"I told him not to do it because Axl was molested by his father when he was two and he believed the charges against Michael Jackson. So I asked Slash, ‘How much are you receiving?’ … and he said, ‘I’ll just receive a big screen television.’ When Axl found out Slash was going to play with Michael Jackson and that the payment was a big screen TV, he was devastated,"Goldstein told Rolling Stone Brazil. "He thought Slash would support him and be against all abuse. From Axl’s point of view, that was the only problem. He could ignore the drugs and the alcohol, but never the child abuse."

Goldstein, however, ends his story on a somewhat hopeful note: “Slash would have to apologize for the episode with Michael Jackson. And I really believe … I’d be the manager to reunite them. I don’t think anyone else could do it.” 

Good luck with that.