Nicole Richie Mourns DJ AM

Friends of Nicole Richie say she was devastated when she learned of ex-fiancé DJ AM's (Adam Goldstein) death over the weekend from an apparent drug overdose. Yesterday, just one day after Goldstein was laid to rest, Richie, along with hundreds of Goldstein's family and friends, attended a memorial service for the DJ at the Hollywood Palladium in Los Angeles.

The memorial was set up as an "open 12-step meeting" in honor of the DJ's struggles with addiction over the years. Richie, 27, arrived to the service 15 minutes early and hugged Goldstein's parents before taking a seat in the front row. Richie and the DJ dated for several years starting in 2004. She cried throughout the service and kept her sunglasses on throughout the entire two hour memorial.

The 36-year-old DJ's death on Aug. 28 has not been officially determined, but an NYPD source revealed that Goldstein had oxycontin pills in his stomach and that his body was found alongside a bag of crack and a crack pipe.