Kristin Cavallari Says Falling Out with Best Friend Involved Cheating Rumors with Jay Cutler

Kristin Cavallari is finally shedding some light on her falling out with longtime friend Kelly Henderson.

On the season 3 debut of her E! reality show, Very Cavallari, the former Laguna Beach star revealed the two hadn’t spoken all summer in the aftermath of the rumor that Henderson and Cavallari’s husband Jay Cutler were having an affair. Henderson, a celebrity stylist and glam specialist, was a major part of seasons 1 and 2, and some fans on social media had begun speculating that something was going on between her and Cutler.

“The biggest change in my personal life is that my best friend Kelly and I haven’t talked in two months,” Cavallari, 33, said in a confessional on Thursday’s season 3 premiere. “We’ve had a major falling out and it’s just been breaking my heart.”

“When season 2 was airing, there was a lot of talk on social media about Jay and Kelly having an affair,” she continued. “Not for one second have I ever thought that it was true. It wasn’t the actual accusations of them having an affair that made me upset, it was how Kelly went about it.”

According to Cavallari, Henderson “kept talking about Jay on social media,” which was only “adding fuel to the fire.”

“I kept trying to reach out to her and talk to her about it and tell her how I was feeling, and instead of her just owning her side of it and being like, ‘I’m sorry. Oh my god, that was never my intention,’ or whatever, she kept giving me pushback and would get really defensive,” Cavallari said. “And then she literally just stopped responding to me. That, to me, is such a slap in the face. You don’t care? Good to know.”

RELATED: Kristin Cavallari Says She and Jay Cutler Speak ‘Different Languages When It Comes to Conflict’

The Uncommon James owner got together with two other close friends, colorist Justin Anderson and corporate consultant Stephanie “Biegs” Biegel, to fill them in on what was going on.

“I literally haven’t talked to Kelly at all — honestly, probably two times in the last six months and it’s only been about the show,” Cavallari told them. “She was accused of having an affair with Jay last season of the show, which, fine, I get it — that’s a lot for her to deal with, too.”

“But she wanted to post something about it. I was like, ‘Don’t post anything about it! That’s the last thing you do,’ ” she continued. “Why do you want to post about that? To get more attention about it. If I was accused of having an affair with your husband, I wouldn’t say his f—ing name on social media. Like, like come on! It kind of blows my mind.”

Cavallari told Anderson and Biegel that she had sent Henderson an email, which wasn’t well received.

“I was like, ‘Here’s how your actions have affected me.’ And she wrote me back and she was really defensive,” Cavallari said. “The point is I feel very used. I care way too much about her to just be like, ‘Oh, f— her,’ or whatever. But I’m not willing to just let it go. And I don’t know if I’m ready to just move on from it.”

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Cavallari also sat down with Cutler, 36, to discuss the situation, admitting it had left her “emotionally drained.” He suggested his wife “take a little bit of time and space,” then meet with Henderson to try to smooth things over. Cavallari agreed and said she hoped they could “come back around.”

“[Reality TV] totally messes up friendship and I know that, that’s why I was nervous going into it,” Cavallari said of her show. “But I thought Kelly was the last person who would become affected. I’ve completely lost my friend.”

“Kelly was in my inner circle — she was one of my people,” she continued. “So this has been really hard on me.”

Henderson has not directly addressed the feud, though a sneak peek at the rest of the season teased an emotional sit-down between the two women.

And Henderson did appear to acknowledge the drama with a cryptic Instagram post on Thursday that read, “Take a deep breath and remember who the f— you are.”

Appearing on PeopleTV’s Reality Check this week, Cavallari wouldn’t go into specifics about their falling out, but admitted it hasn’t been easy.

“I felt very disappointed in one of my best friends,” she said. “She’s been one of my best friends for almost eight years, so it has been extremely heartbreaking. … Talking about it, it’s still really hard for me. But I want everyone just to watch it and form their own opinion.”

As for whether a reconciliation is in the cards?

“You’ll see it on the show,” Cavallari said. “There is definitely some sort of resolution there at the end that you’ll be able to see.”

Very Cavallari airs Thursdays (9 p.m. ET) on E!