The Situation Is No Longer Sober: Source

Mike 'The Situation' Sorrentino on January 11, 2012 in New York City.  Neilson Barnard/Getty Images

Mike "The Situation" Sorrentino is in a tough situation.

The Jersey Shore star, 30, who entered rehab for substance abuse in March, "isn't sober anymore," a source tells Us Weekly in the new issue, on stands Friday.

PHOTOS: Wildest Jersey Shore moments

Indeed, at West Hollywood's London hotel September 26, a witness saw him "downing so many cocktails, he could barely stand." (His rep responds, "He has not been drinking.")

In his first interview after completing an in-patient treatment program, Sorrentino told MTV News, "Ever since I've been out, I'm not gonna lie . . . it's not easy."

The insider adds to Us that the Sitch is stressed the MTV series is ending: "Mike's freaking out about what he's going to do after the show."

The final season of Jersey Shore premieres with a double episode on Thursday, Oct. 4 at 10 p.m. EST on MTV.

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