An insider tells Star, "[Lindsay] left the hospital [after her appendectomy] with several painkillers on her; that was her downfall - she was using the painkillers and continuing to go out and drink. She woke up each morning exhausted and feeling sicker than ever." As Page Six stated, Lindsay hit rock bottom when she passed out in the hallway of the Beverly Wilshire early on Tuesday morning following Prince's Golden Globes afterparty.

Her family was already worried about her because of her lackadaisical work ethic - and so were the producers of her current project I Know Who Killed Me. Star's source says, "The movie executives said they had a major issue with getting her insured for the film and threatened to sue her for between for between $3 million and $5 million for the delays her constant absences were causing on the set."

Between her blackout and the movie problems, Lindsay's camp had had enough. The snitch says, "Lindsay's family and other people she works with sat down with her [Tuesday] night and convinced her she had to go into rehab to save herself professionally and personally. She couldn't afford to have another letter come out about how she was being unprofessional and missing work on the set." The source revealed that Lindsay's rehab clinic, Wonderland Center, will allow her to leave during the day for filming.

Meanwhile, a reporter from OK! magazine contacted Lindsay on Wednesday shortly after she checked in to Wonderland. Lindsay said, "I'm doing so great…I'm fine. Nothing to worry about. Thank you so much for checking in, I do appreciate it. I'm actually watching American Idol at the moment and laughing so hard!"