How Newly-Single Renee Zellweger Celebrated Her 42nd Birthday

Renee Zellweger celebrated her 42nd birthday on Saturday as a single gal. The actress' assistant arranged a surprise party for 15 guests at a friend's Manhattan apartment, a source tells Us Weekly.

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Guests included Miramax cofounder Harvey Weinstein and CAA director Bryan Lourd. Her ex-beau, Bradley Cooper, was not present, nor were any other actors. "She was solo and having a great time," a source tells Us.

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Hotelier Andre Balazs was also in attendance; the 54-year-old has been romantically linked to Uma Thurman and Chelsea Handler in the past. According to the New York Post, Zellweger celebrated with Balazs again Monday night at Indochine, a downtown restaurant. A source tells Us, however, "[Andre] an Renee are just close friends."

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Zellweger and Cooper, 36, split in March after over two years together. A source told Us: "She stopped fighting. It was just not working out."

Since their parting, Zellweger's stayed busy: fresh from her split, she hung out with Sandra Bullock at the divorcee's Soho apartment. She also attended Reese Witherspoon's star-studded March 26 wedding to Jim Toth, and sold her posh Upper East side apartments to Leelee Sobieski.