July 21: At party venue Polaroid Beach House, Lohan wore a bikini – and her alcohol monitor. Photo by: Simon Ferreira / Startraks
Falling Apart| Lindsay Lohan
Lohan is, in fact, already a rehab veteran; seven months before her stay at Promises, she spent time at L.A.'s Wonderland treatment center and publicly spoke of attending Alcoholics Anonymous meetings. "It's not uncommon for the newly sober to slip," says Beverly Hills addiction specialist Marty Brenner.

"It's part of the disease." Before she went into Promises, a source close to Lohan told People that her best chance for sobriety was to "really follow the directions of her sponsors and counselors." Those directions vary from person to person and center to center, but the bottom line is always the same. "If you want sobriety, you have to change everything," says Brenner. "You have to change your friends, your crowd, your lifestyle."

Those seem to be changes Lohan was unable to make. Even before she officially ended her treatment program, says a source, Lohan was surrounded by hangers-on who had no interest in the party being over: "If she went away and got [sober], they wouldn't have their late-night clubs, the bottle service, the parties." Some of those enablers, in fact, crashed Lohan's 21st-birthday party in Malibu on July 2. "She's naive and doesn't realize how these friends use her," says a close source who was at the party. A person who knows her well says that Lohan used to regularly ask friends to "pour mixed drinks in her water bottle" so that no one would know she was drinking.
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