March 20, 2007 -- WHICH socialite was conspicuously absent from the front row during Fashion Week because she was in rehab? The bride-to-be went to a "special spa" to conquer her cocaine habit before the wedding . . . WHICH celebrity mom joins her daughter in snorting lines of cocaine? . . . WHICH soulful singer is bulimic? Friends are concerned the stress of having a new album is causing her to throw up her meals . . . WHICH funnyman is having an affair? His wife doesn't mind - she's got her money and her status to keep her company