Rocker Johnny Rotten has likened troubled stars Pete Doherty and Amy Winehouse to his ex-bandmate Sid Vicious. The Sex Pistols frontman believes Winehouse and Doherty are no longer enjoying making music and are committing "a slow suicide" by turning to drugs - just like his close friend and bassist Vicious, who died of a drug overdose in 1979. He says, "You know you can use drugs for entertainment but you should be quiet about it. That shouldn't be your centre showpiece. "There's not much going on in their head with them. They're not thinking. They're not doing this for the right reasons. "They obviously don't enjoy what they're doing. And that's why you turn to drugs. And that's what happened with Sid, he wasn't happy about what he couldn't do. "It's a slow suicide and it's a cry for help because they're in pain, they're in mental pain. And this is a disgusting industry because people just cut you dead. "The general public aren't too wise about what that means to be constantly in the limelight. It's a pain in the f**king arse."