Sex Tapes, Cheating & Divorce! 'The Hills' Most Shocking Relationship Scandals Ever

Lauren Conrad and Heidi Montag — their friendship was filled with so much drama that they may have well been considered a couple. It's been a decade since they broke up and after hundreds of fights about Montag spending all her time with Spencer Pratt, the duo finally called it quits. Montag moved out of the apartment she shared with her BFF and into a condo with him.

"You KNOW what you did!" Those famous words uttered by L.C. and the fight of the ages on the reality series which epitomized the complicated love-hate relationship between the frenemies. As fans know, the epic scene went down in season three when Conrad put Montag on blast outside an L.A. nightclub about some nasty rumors that had circulated over the summer. Montag and Pratt were accused of spreading rumors that Conrad made a sex tape.

And thus brings us to Spencer and Heidi, in the mid-2000s, the duo — more commonly known as Speidi — gained widespread notoriety by playing the villains on show. Unlike all the other cast members, their love surprisingly proved to be true.

Aside from a quickie divorce — which Pratt actually admitted was a publicity stunt — Speidi were one of the very few couple's to escape the reality show curse of failed relationships. They have now been married eight years and are expecting their first child together.

Then there was Spencer's sister Stephanie, who dated motocross beau Josh Hansen — or at least she thought she did. The unlucky in love reality star first met Hansen through Brody Jenner at a Hollywood nightclub on one of the last episodes. The duo continued hanging out post-Hills and walked the carpet together at the show’s series finale last month. The romance was short-lived and perhaps even a publicity stunt as after Stephanie "announced" the breakup, Hansen proceeded to deny they were ever dating.

Who could forget Audrina Patrdige and infamous bad boy Justin "Bobby" Brescia — quite possibly the most tumultuous pair in reality TV history. Brescia and Patridge dated on and off from 2007 to 2010 and the nearly every episode of the series featured a fight between the couple.

What's a show without a little love triangle? Somewhere in between the time Patridge and Justin were canoodling, BFF Conrad swooped in on the action as rumors circulated that the two were hooking up behind Patridge's back. She confronted Conrad at a night club where the duo duked it out. L.C. denies hooking up with J.B. to this day.

To make the storyline stronger, show villain Kristin Cavallari then honed in on fellow villain Justin.

Everyone knew Cavallari was trouble, we just didn't know how much until she pulled this sinister stunt in season five. Of course, Audrina wasn't having it and when she saw Kristin make moves on Justin at a party things really got heated. "It's girl code. You just don't go there," she yelled at Kristin.

Conrad finally thought she met her match when she rekindled things with a high school romance, Jason Wahler. To her dismay, the spark burned quick. After forgiving Jason once for cheating on her with his ex, Jessica, it was his own jealousy that ultimately led to the couple's undoing. As showcased in an episode during New Year's Eve 2005, Wahler found out Conrad got a call from a guy she used to hangout with. This didn't sit too well with him so he kicked L.C. to the curb.

Conrad wasn't ready to give up on love just yet. She fell hard for Brody Jenner. Unfortunately, Jenner was still dabbling in his Playboy stage and couldn't settle down. The show's alternate ending gave viewers hope that the smiley couple could have lasted, but they just weren't meant to be.

Speaking of Playboy behavior — another detail that led to the couple's demise was Conrad's other BFF Jen Bunney. Bunney and Conrad fought over Jenner when Bunney hooked up with him behind Conrad's back while the two were roommates.

After taking a break from the dating game for a bit, Conrad fell again — but this time it was Doug Reinhardt. Lauren and Doug dated for a bit in high school and tried to reconnect their flame years later while they were both filming the show. But the spark blew out quick. Plus, when Lauren heard that Doug was also trying to date Stephanie Pratt, she shut down the possibility of ever starting things up again.

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