The famous mother of 14, who gave birth to octuplets three years ago, entered the Chapman House Treatment Center last week for treatment of “anxiety, exhaustion and stress,” her rep told the Daily News. Nadya Suleman, 37, left her record-busting brood in the hands of three nannies, two friends, a driver and security while she’s gone an estimated 28 days, the rep said. “Ms. Suleman has been taking Xanax that was prescribed by her doctor to deal with her anxiety, but she felt she needed a treatment program to help with her recovery,” manager Gina Rodriguez said Tuesday. “She was prescribed Xanax for her anxiety attacks, she was not addicted to it. She has an overabundance of stress and exhaustion and wanted to deal with it with out prescription drugs,” Rodriguez said. Although the rehab, based in Orange, Calif., offered to pick up the tab, the star of a recent self-pleasuring video opted to pay her own way, the manager said.