Kristin Cavallari and Jay Cutler sent shockwaves through the entertainment world when they announced they were divorcing after 10 years together and nearly seven years of marriage, but according to People magazine, the former couple had issues connecting long before calling quits on their union.

"Kristin has been so unhappy for so long. Her marriage has been struggling for at least three years," a source linked to Cavallari told the outlet on Thursday. “She just wants to be happy and to be a good mom. They tried to make it work for the kids, but Kristin realized Jay is not going to change.”

Meanwhile, an insider privy to their TV relations relayed that the reality show star and the former NFL quarterback "were not suited for each other, even in the beginning" and spending time apart during their marriage due to their respective careers was simply no match for the inevitable.

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"They were both so busy with their careers that it was often hard to find time to be together," the source explained. "They lived apart a couple of times during the marriage. This takes a toll on any romance no matter how promising things looked to others."

Cutler and Cavallari tied the knot in 2013 and share children Camden, 7, Jaxon, 5, and Saylor, 4. The pair has appeared together on the E! reality show “Very Cavallari" since 2018.

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On Sunday, they announced their split via social media, saying they had “grown apart” but maintained "We have nothing but love and respect for one another.”

The same television insider also told People that the “Laguna Beach” alum and Cutler experienced a shift in their relationship after having children together.

"Each is a good parent, but they seem to do better jobs with the children when they parent them separately," the source said, adding, "They have too many disagreements over style and what is right or wrong when they're together.

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"Like any couple, they want to stay together for the kids," the insider noted. "But once the spell is broken and the romance has fizzled out, it's just a waiting game to see how long you can stay together until an explosion occurs. That is where they were."

A third source echoed the sentiment, telling the outlet the marriage was a ticking time bomb and was a "long time coming" since the couple "simply were not getting along."

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Representatives for Cutler and Cavallari did not immediately respond to Fox News’ request for comment.