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Katy Perry is said to be "devastated" over the death of her ex-boyfriend, "Sons of Anarchy" actor Johnny Lewis, who was found dead in a driveway from an apparent fall in Los Angeles.

A source close to Perry, who dated Johnny from 2005 to 2006, told US Weekly that she and Lewis had "good times," but added that the actor was "trouble" and that Katy "had to separate from him . . . to get ahead and focus on her career."

"It's really sad. She could never help him and couldn't [let herself] go in that direction," the source said, adding that Katy's songs "The One that Got Away" and "Circle the Drain" are partly about Lewis.

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Perry's relationship with the actor was "a time in her life she cherishes," the source said.

According to the LAPD, officers were called to a home at Wednesday morning after neighbors reported hearing screaming. They found Catherine Davis, 81, dead at the scene from unspecified trauma. Outside, police discovered Lewis' body in the driveway.

Police believe that Lewis killed the woman's cat and beat her to death.

Davis played Kip "Half Sack" Epps in the first two seasons of "Sons of Anarchy" and appeared alongside Dakota Fanning and Kristen Stewart in "The Runaways" in 2010.