Britney: It Was All Postpartum Depression

Britney Spears is doing time in rehab, but she's not toeing the line on why she's there. Spies at the pricey Promises clinic tell US Weekly that she caved to pressure from her family and manager to check herself in, but she's not copping to a substance abuse problem.

Her own diagnosis for the partying binge and bizarre behavior that led to the very public loss of her hair: postpartum depression. US reports that the resentful Spears has been a less than well-behaved patient. "She's been talking on her cell phone too often. She's been reprimanded... She's actually ducked out of rehab to go shopping for several hours." (More Britney Spears stories.)