Gossip of an affair between Cavallari's husband and Henderson permeated the previous season of "Very Cavallari."
Fans have been dying to know what went down with former BFFs Kristin Cavallari and Kelly Henderson.
And they didn't have to wait long, as the third season premiere of "Very Cavallari" on Thursday had the Uncommon James mogul open up about the details surrounding their friendship break-up.
"The biggest change in my personal life is that my best friend Kelly and I haven't talked in two months," Cavallari admitted in a confessional. "We've had a major falling out and it's just been breaking my heart."
Later, Cavallari confided in her two other friends, Justin Anderson and Stephanie "Biegs" Biegel, that Henderson had only reached out to talk about the show's production schedule and the cheating rumors regarding Cavallari's husband Jay Cutler and herself.
"When season two was airing, there was a lot of talk on social media about Jay and Kelly having an affair. Not for one second have I ever thought that it was true," Cavallari said. "It wasn't the actual accusations of them having an affair that made me upset, it was how Kelly went about it."
She explained how Henderson would constantly bring up the rumors online, adding "fuel to the fire," which made Cavallari believe it was in self-interest.
"Why do you want to post about that? To get more attention about it," asked Cavallari to Anderson and Biegel. "If I was accused of having an affair with your husband, I wouldn't say his f--king name on social media. Like, come on."
Cavallari attempted to diffuse the situation by reaching out to Henderson, with no luck.
"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 push back and would get really defensive," Cavallari explained. "And then, she literally just stopped responding to me."
Clearly, this upset Cavallari as the two have been very tight for the last few years.
"The point is, I feel very used. I care way too much about her to just be like, 'Oh f--k her' or whatever," the star revealed. "But, I'm not willing to just let it go. And I don't know if I'm ready to just move on."
"Like, my best friend could care less about me, unless it has to do with what she can gain from me and you," she told her Cutler.
"I've completely lost my friend," the former MTV star lamented.
Henderson may explain her side of the fallout, as she is to return to the show next episode.
Watch the drama go down on "Very Cavallari" Thursdays at 9 p.m., only on E!
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