Troubled socialite Nicole Richie has been forced to seek professional help, entering rehab for postnatal depression , NW reports

"Nicole's not completely happy with her life," tells a pal.

"She just misses being out at parties and having the chance to get out all the time. She feels like she's always at home."

With the news she's secretly battled chronic depression — a debilitating condition that first saw her turn to drugs as a form of escape — ever since she was a child, friends fear history could now repeat itself.

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