The former 'The Hills' star has revealed the show was almost entirely scripted and she didn't mind because she said it was fun to act out all the drama on the MTV series, which ended two and a half years ago, but says her rivalry with Lauren wasn't fake.
She told Bravo's 'Watch What Happens Live' the show was ''pretty fake'' and said the show's producers ''pretty much'' told everyone what to say.
She explained: ''Fake relationships, fake fights... but it was fun, because you're acting. And that was more fun for me.''
But the 25-year-old - who welcomed her first son, Camden, with fiance Jay Cutler earlier this year - insists her drama with Lauren felt very real although thinks producers stirred the tension between them.
She said: ''I feel like they put things in our heads. We were 17 and 18, and they made it a lot worse than it was.''
Kristin also revealed that she never dated Audrina Patridge's onscreen boyfriend Justin Bobby, despite appearances on the show.
She said: ''I think I made out with him once and that took a lot of convincing.''
Kristin's rant comes just days after Lauren, 26, insisted most of the series was real.
She said: ''I think the story they told wasn't a dishonest one. The way they did it sometimes was.
''They aren't going to be there for everything. Sometimes two characters will get into a fight, and that's important to the story line. The [producers] need that re-enacted.''