Jessica Simpson's hospitalization due to "months of hard drinking"

Jessica Simpson's recent hospitalization was down to months of hard drinking with boyfriend Tony Romo, Star magazine claims, citing sources close to the former reality TV star.

Simpson, 27, was rushed to Los Angeles' Cedars-Sinai Medical Center on March 28, and remained there for four days. Her reps said she was being treated for a "kidney infection," but sources close to Jessica tell a different story.

Her health problems, say sources, were "brought on by drinking an obscene amount of alcohol.

"She was treated for a kidney infection, a bladder infection and a urinary tract infection."

Jessica also demanded the doctors give her a pregnancy test -- because she was "three weeks late" for her period.

"She was a nervous wreck," says the insider. "She was three weeks late and convinced she was pregnant. She was feeling really weak and really scared. She was unraveling."

The former 'Newly Weds' star has dated a string of men since her 2006 split from singer Nick Lachey, including musician John Mayer. But after hooking up with Dallas Cowboys quarterback Tony in November, insiders say her partying and drinking is spiraling out of control.

"She used to keep her drinks to a minimum, because she's very conscientious about the calories," says a source. "But Tony and his buddies really party hard, and I think they expect Jessica to keep up with them. But she is like a third of their weight and just can't hold as much as they can."