Mary-Kate Olsen on party binge since her lover Heath Ledger died tragically

Following one recent night of clubbing in L.A., the twin was so out of it that she collapsed in a public parking lot and then spent a short time in a holistic health spa to detox. But that didn't slow her down, and insiders now fear she's out of control and needs more treatment — fast!

"Mary-Kate seriously needs to get to rehab, but she doesn't think she has a problem," says a source. "She thinks she's young, hip and entitled to live her life as she sees fit. But it's affecting everything."

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