Denise Richards has a new boyfriend. The actress — who’s divorced from actor Charlie Sheen and has previously dated rocker Richie Sambora — has been quietly romancing Motley Crue bassist Nikki Sixx, according to Us Weekly magazine.

“They have been neighbors for years. They have a lot in common and are taking things slowly,” a source said.

Richards, 39, and Sixx, 52, had breakfast at Marmalade Cafe in Calabasas, Calif., on the morning of Dec. 12.

“Nikki was telling stories, and Denise was laughing,” says a witness.

Sixx, a former heroin addict, has been married to two Playboy models and romanced Kat Von D from 2008 to January 2010