Plagued by self-doubt and popping prescription pills, Demi Moore, 49, enters a treatment facility following a 911 call that led to her emergency hospitalization. Now undergoing treatment at an undisclosed facility, this week's issue of PEOPLE examines the problems that extend far beyond the "exhaustion" that Moore's rep cited in a Jan. 24 statement. A source close to the situation tells PEOPLE, "Her friends were really scared." Another source says, "She needs help and I hope she gets it. I hope it's not too late."

The hospitalization capped months of extreme weight loss and erratic behavior that intensified around the end of Moore's six-year marriage to actor Ashton Kutcher, 34, in November. "She's embarrassed that her issues got out," says another source who knows Moore's inner circle. For a star who has long gone to drastic lengths to maintain her image as the platinum standard of age-defying beauty, "appearances are paramount," says the source. "What people think of her and how she comes across is so important to her, so this is devastating."

Once Hollywood's highest-paid actress, the charismatic and "ragingly ambitious" star – as her first publicist, Michael Levine, describes Moore's early drive – had become a fragile wisp, tormented by insecurities about her body and age as things with Kutcher fell apart. "As Demi got older, she convinced herself that she needed to stay young and skinny to remain attractive to her husband," says a source who knows the former couple. "She needed reassurance all the time that she was hot and sexy. She was not the person Ashton fell in love with anymore."

During the 911 call on Jan. 23, when asked what drugs Moore had taken, her friend says the actress had been "having some issues lately with some other stuff." Multiple sources tell PEOPLE that they had suspected that Moore's "issues" included her use of prescription drugs. She took pills to "curb her appetite," says the source who knew the couple, who also saw the star with a bottle of Adderall, a stimulant used to treat Attention Deficit Hyperactivity Disorder: "When she took the pills, she wouldn't be hungry. It was a way of keeping her weight in check." Adds another who has known Moore for 30 years: "She's been a mess for months…She was always fixated on being young, and the only thing that tied her to that, as she got older, was her marriage to a younger guy and hanging around young people."

Demi Moore was down to a diet of Red Bull and not much else, say several sources. During the weekend of the Golden Globes in mid-January, "She looked frighteningly skinny," says a Hollywood insider who saw her wearing a sleeveless dress. "You could see everything – the mechanics of her body," adds the insider, who thought her appearance seemed like "a cry for help."

Those close to Moore hope that she is finally on her way toward getting better. Her daughters with ex-husband Bruce Willis (Rumer, 23, Scout, 20, and Tallulah, 18) "are doing okay," says a close source. "They're there for each other, and Bruce has been there for them…They're all going to help their mom, but ultimately this is something she needs to work through by herself." It's a sentiment echoed by Moore's friends as well. "They're happy she's getting treatment," says one insider. "They want her to get back to being the healthy, vibrant Demi they love – and miss."


Check out Demi's story at PEOPLE.com in the new issue, on newsstands now!


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