Reports suggest the rumors had nothing to do with their divorce decision, however.
Before Kristin Cavallari and Jay Cutler announced they were divorcing after 10 years together on Sunday, the two were very candid about their marriage "issues" and even cheating rumors on the ex-couple's reality show "Very Cavallari."
Anyone who watched the most recent season knows Cavallari and former best friend Kelly Henderson had a nasty falling out, following fan speculation she and Cutler were having an affair. While Cavallari herself said she never believed any of the rumors -- which Cutler and Henderson also denied -- she was not thrilled with Henderson's general reaction to the gossip.
On the season premiere, Cavallari explained how Henderson would constantly bring up the rumors online, only adding "fuel to the fire" instead of trying to squash it. "Why do you want to post about that? To get more attention about it," said Kristin. "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."
"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."
Kristin claimed Henderson had "never once" said she was sorry for how the situation escalated. The last interaction viewers saw between the two former friends was Cavallari texting her one final time. According to Cavallari, the text read, "I miss you and this has been absolutely killing me. I'm sorry, I know I'm tough when I'm hurt. I love you and we need to fix this." Kristin said Kelly never responded, which Cavallari said was "the final straw in the friendship."
According to sources speaking with both PEOPLE and E!, the cheating rumors had "nothing" to do with their decision to separate.
"With great sadness, after 10 years together we have come to a loving conclusion to get a divorce," both Cavallari and Cutler shared on their respective social media pages Sunday. "We have nothing but love and respect for one another and are deeply grateful for the years shared, memories made, and the children we are so proud of. This is just the situation of two people growing apart. We ask everyone to respect our privacy as we navigate this difficult time within our family."
The announcement came after Cavallari also spoke about some of the "ups and downs" in their marriage on a later episode of "Very Cavallari."
"Jay has been great, yes. From the outside, things are so perfect and things are so great. But actually, they're not. And that sucks," she said in an April episode. "It sucks. That's the thing, though, with marriage ... it's ups and downs."
Saying that there's "no such thing as a perfect relationship," she admitted she and Jay "have problems." Cavallari added, "I've always been very vocal about that. We have to work at our relationship, so hearing him say that we're perfect is kind of silly to me. We definitely have issues."
The two announced their split following a vacation together to the Bahamas, which became a three-week ordeal and sparked backlash as they stayed longer than anticipated during the coronavirus pandemic.
According to a PEOPLE source, the two "already knew they were splitting up" before the getaway.
The exes share sons Camden, 7, and Jaxon, 5, and daughter Saylor, 4.