Why 'RHOBH' Stars Kyle Richards and Lisa Vanderpump Aren't Friends Anymore

Since Real Housewives of Beverly Hills first debuted on Bravo in 2010, Kyle Richards and Lisa Vanderpump have been the best of friends. Sure, the women's relationship has suffered a few bumps and bruises along the way, but for the most part, their bond has seemingly remained indestructible—that is, until now.

Trailers for Season 9 of the reality show hinted at a huge fallout between Richards and Vanderpump, and in pre-season interviews, both women noted they were no longer on speaking terms. Vanderpump actually hasn't spoken to majority of her RHOBH cast after she stopped filming halfway through the season, and it's unclear whether or not the reality veteran will appear at the RHOBH Season 9 reunion.

So what's all the beef about? Well, all of the fallouts so far this season stem around a dog, Lucy Lucy Apple Juice, and a gossip-fueled scandal referred to on social media as PuppyGate.

It all started when RHOBH star Dorit Kemsley adopted Lucy from Vanderpump's animal rescue charity, Vanderpump Dogs. Kemsley claimed to have given the dog to another woman after determining the pup was not "the right fit" for her family—she said in a Bravo interview that Lucy bit her children and her husband Paul "PK Kemsley." However, the other woman ended up passing the dog off to another shelter, who then identified the animal as a Vanderpump Dog's rescue and returned it back to the charity.

Originally on Season 9, the story was spun amongst the cast as if Kemsley purposely gave the dog to a kill shelter. When that turned out to be false, it was determined among the women Vanderpump conspired the story to make Kemsley look bad, although the restauranteur adamantly denied having any role in the rumors.

On episode 8, which aired Tuesday, the drama only intensified for Vanderpump after Kemsley caught wind of a Radar Online article that painted her out to be a villain in Lucy's fate and a separate TMZ article, in which Vanderpump was quoted as defending Kemsley.

Kemsley, along with several other castmates, believed Vanderpump was the source behind both of the stories, while Richards reluctantly admitted the stories did seem to point in Vanderpump's direction. Being the closest one to Vanderpump, Richards decided to visit her friend to get to the bottom of the situation.

"I'm dreading going to Lisa's house. In the past, I defended her. But this time, it's very different," Richards said during a confessional. "As difficult as it is, I have to be honest with Lisa, and I know Lisa's going to be upset. If I were to look at my daughters and how I'm raising them, I would tell them, 'You have to defend what's right.' And that's what I'm trying to do right now."

Vanderpump was highly offended when Richards suggested the articles came from her camp. "You think I'm going to give a story to Radar Online and then I'm going to go to TMZ and refute a story I've given to Radar Online? Do you think I would give a story to Radar Online about Dorit?"

When Richards suggested perhaps Vanderpump cared "more about your image than your friendships," all hell broke loose.

"Wow, this is a big shock to me. This changes everything. I've done nothing wrong. Just because you accuse me, I am not going to say, 'Yes I did something' if I didn't do it," Vanderpump snapped. "I'm a woman with integrity who stands up for what's right. I could have thrown her under the bus. But I'm done. I'm done with you, too."

Although Richards tried to continue the conversation, Vanderpump asked her to leave her home. When she didn't, Vanderpump's husband, Ken intervened.

"You're supposed to be her friend. You cannot be her friend when you say something like that. She would never say that about you. You're a f**king liar and you're not my friend or her friend. So you get out. Please go. Please go. Join the gang … ganging up on her. … Twelve years of friendship, done!" he said.

Richards leaving marked the last time the castmates have spoken.

In a Tuesday interview with Entertainment Tonight, Vanderpump said she had no plans of reconciling with Richards despite Richards telling LIVE! with Kelly and Ryan she hoped to clear the air with Vanderpump during her February appearance.

That doesn't necessarily mean the women are truly done with each other, though.

Despite only being present for half of RHOBH Season 9, 58-year-old Vanderpump admitted during a separate ET interview that her appearance at the reunion special was still up in the air.

"[The reunion's] not for two or three months, so I have no idea how I'll feel then," she said. "But they said I wouldn't show up on the red carpet [at the premiere party] didn't they? I think it was Lisa Rinna who was tweeting, 'You motherf**kers better f**king show up.' I mean, who talks like that? But I was there, yes."

If she does show up, the odds of her having to speak with Richards about the situation are incredibly likely, although that won't mean they'll end up as good of friends as they were in earlier seasons.

Real Housewives of Beverly Hills airs on Bravo on Tuesdays at 9 p.m. ET.