The reality TV star, 33, opened up about her split from the former quarterback, 37, in an interview with People released Sept. 23.
For years, fans watched the duo's relationship play out on Very Cavallari. And while Cavallari and Cutler experienced several ups and downs over the course of three seasons, many believed they were the perfect couple.
"I always thought it was interesting when people would refer to us as 'couple goals,'" Cavallari told the magazine "I was like, 'If you guys only knew.'"
The Laguna Beach alum admitted they "kept a lot of stuff private" and that the end of their marriage "didn't happen overnight."
"We tried really, really hard for years and years," she said. "It was the hardest decision I've ever made."
In terms of what led to the breakup, the Uncommon James founder suggested they just grew apart.
"Every relationship has their stuff," Cavallari revealed. "I met Jay when I was 23. I was a baby. Jay and I had so much love for each other, but we grew up. When you work at something for so many years and nothing's changing, I think you have to just make a decision. We all want to be happy."
In the weeks following the split, which they announced in April, the exes dealt with everything from bombshell filing claims and intense public scrutiny to a custody agreement and a move. However, Cavallari told People she and Cutler have been able to work together to co-parent their three children: Camden, 8, Jaxon, 6, and Saylor, 4.
"I still care so much about him and talk to him almost every day," she said. "We have three kids together. He's going to be in my life forever."
Their decision to split came about a decade after Cavallari and Cutler first sparked romance rumors in 2010. By 2011, Cutler had proposed. However, the two ended up calling off the engagement later that year. It wasn't long before the stars decided to give their relationship another shot and got engaged again months later. They finally wed in 2013.
Now, Cavallari is looking forward to her new chapter.
"I'm proud for making this decision," she said. "It wore at me every single day for years. I feel like my whole world is opening up now because of it, and I'm just feeling the best I've felt in a really long time. I'm really excited about the future all around."