"I'm excited about the next chapter," Cavallari exclusively told ET's Lauren Zima at the Casino on Catalina Island. It's the first time she has spoken about her split from Cutler on-camera.
"I have hard days, without a doubt, and right now I'm really just focusing on my kids and making sure that my kids are good. That's my only priority at the moment, and they're handling it well," she revealed. "I'm just trying to stay positive and focus on all of the positive things. But I have sad days, without a doubt."
Cavallari and Cutler, who were married in 2013, announced their breakup in a joint statement on Instagram in April. The news came soon after the pair's three-week "isolation" in the Bahamas with their kids and two friends, but Cavallari said they had been considering their split for a while -- two years, to be exact.
"It was not an easy decision, obviously," Cavallari admitted. "It was something that I truly thought about every single day for over two years."
"It was the hardest decision that I have ever made," she added. "But I don't know, my mom [Judith Spies Eifrig] used to say, 'You'll know when it's time.' I feel like that was true. I knew. And that's that."
While the pair's split may have been a shock to fans, to Cavallari, it didn't come "out of left field." The couple "worked hard" on their marriage, for the sake of their three kids -- 8-year-old Camden, 6-year-old Jaxon and 4-year-old Sailor.
"It just didn't work. I met Jay when I was 23. I was a kid, but we tried. We tried everything, and Jay and I had so much love for each other. No one could ever take that away from us," Cavallari said. "But at the end of the day, we weren't happy."
"I think life is too short," she added, noting that her parents' divorce allowed her to see her mom in a "really happy, healthy marriage." "That's actually what I want. I want my kids to see me happy. I think that's important."
Cavallari announced the end of Very Cavallari in May, just one month after filing for divorce. Her and Cutler's relationship was featured on the show, but they kept most of their "tough times" away from the cameras, she said. She decided keeping her divorce away from the cameras was also for the best.
"I didn't want to talk about my divorce on camera and have to expose that. I really think that some things should be kept private. The situation I had with my really good friend on Very Cavallari got really blown out of proportion and I had to talk about it way more than I ever would have," she said of her falling out with Kelly Henderson, who was rumored to be having an affair with Cutler while season 2 of Very Cavallari was airing. Henderson has denied ever being romantically involved with Cutler, or having anything to do with his and Cavallari's divorce.
"If it was that hard [going through a falling out] with a girlfriend, I do not want to go through that with a divorce," Cavallari told ET. "It would have gone horrible. It would have been awful and I had so much anxiety about it."
The Laguna Beach alum said the only reason she started the show was to promote Uncommon James, and with three seasons completed, she felt like she accomplished that goal. "Actually before we started it, I said, 'I really want to do three seasons,' and it just kind of worked out that way. So, everything works out in life," she expressed.
Cavallari feels "relief" that she's been able to move on from her split from Cutler, and it won't play out on TV. Though she'll make a brief appearance on The Hills: New Beginnings, she's not interested in doing another reality show about her life. She, however, is open to possibly doing a cooking show. Her cookbook, True Comfort, releases on Tuesday.
"I would love to do a cooking show. I feel like that would be fun," she said. "I am just at the point in my life right now where it has to fit into my life... I really love where my life is at right now, between my kids and the office."
True Comfort definitely fits into Cavallari's life. She calls the book a "true representation of how I eat on a daily basis."
"Everything is healthy. The cookbook is gluten free, it has limited dairy, no white sugar, no white salt, no white flour. That's how I eat on a daily basis," she shared. "I think there's been this stigma that comforting food is really fattening, but I think if you make certain ingredient swaps, you can eat that stuff every day."
"True Comfort is the follow-up book to True Roots, which is very much a spring-summer lighter kind of cookbook. True Comfort is full fall-winter, comfort food that just takes us back to our childhood or can really turn a bad day around," she described. "Comfort food is where our hearts, are especially now. I think we want comfort food more than ever."
Cavallari has also found comfort in her new collection for Uncommon James, which features chains, chunky statement pieces and "a whole butterfly story."
"Butterflies are incredibly trendy at the moment, but butterflies have always been a comforting, nice sign for me as well when I am going through tough times," she explained. Cavallari connects butterflies to her late grandmothers and her late brother, which "just makes me feel really at peace," she said.
Cavallari designed the collection right at the start of the coronavirus outbreak. The photo shoot was conducted on Catalina Island, where she hadn't been since her high school trip with her Laguna Beach co-stars.
"I took my kids to Laguna Beach... Stephen and I hung out and posted a photo, we had a great time seeing each other. It had been years," she shared. "But nothing romantic is going on. I know that's what everyone is trying to get at, but Stephen and I have always remained really good friends."
As for whether she and her kids could make a permanent move to her former OC stomping grounds, Cavallari said that's not in the cards.
"I loved Laguna, but I really love Nashville, and my kids are really happy there," she shared. "I moved around so much as a kid, I would not want to do that to my kids, just bouncing them all over the place. They are happy, I am happy and I am just going to stay the course."