'Hills' Star Blames Skinny Co-Stars For Making Her Bulimic

“Hills” star Stephanie Pratt is opening up about her struggle with bulimia and the agony of working with her skinny co-stars, all while posing in a bikini on the cover of Us magazine.

The 23-year-old star – and sister to reality television’s most hated man Spencer Pratt – says the show is the reason that she was found herself on a downward spiral of bingeing on 5,000 calories a day followed by intense purging.

In 2007, after first joining the cast, the size 0-2 Pratt tells Us she was “horrified” when she watched a scene with co-star Lauren Conrad.

“I remember saying, ‘I can’t believe how huge I look walking over to Lauren.”

While she said the producers never put pressure on her to lose weight, Pratt found it “embarrassing working with skinny girls.”

The star also admitted that she tried to kill herself from the pressure, as she recalled a moment where her co-star Audrina Patridge told her she looked better in a bikini with her shirt on.

RELATED: Click here to read the full report from Us magazine.