On Thursday night's season premiere, Kourtney and Kim Kardashian slapped each other after arguing about filming commitments

Has Kourtney Kardashian officially said goodbye to her family’s reality show?

On Thursday’s season 18 premiere of Keeping Up with the Kardashians, a confrontation between Kourtney and her sister Kim Kardashian West got shockingly physical. The argument stemmed from tensions between the two that have been simmering since last season over Kourtney’s boundaries when it comes to filming. Kim was frustrated with her sister’s work ethic — or, in her opinion, lack thereof.

Last fall, Kourtney, 40, confirmed she had taken a step back from the show to focus on her family. But now, she appears to be hinting that she quit for good. Ahead of the premiere, she addressed her fans on Instagram, saying she had finally found “the courage” to make important changes in her life.

Kourtney Kardashian
Credit: Vivien Killilea/Getty Images

“The season premier [sic] of season 18 airs tonight on E!” she wrote. “These first two episodes are hard for me to watch but it is in our darker moments that the growth happens. I finally had the courage to change what was no longer bringing me happiness and putting my time and energy into that which is. Choose happiness!”

And on Twitter, she fired back at a fan who complained that she “just needs to quit the damn show.”

“I did. Bye,” she wrote.

Her rep did not immediately respond to PEOPLE’s request for comment.

In a recent interview with E! News’ Jason Kennedy for an episode of In the Room, Kourtney reflected on her current chapter in life, saying her three kids with ex Scott Disick will always be her “top priority.”

“I was feeling just really unhappy,” she admitted. “I felt like I was on a hamster wheel. I felt like something needed to change.”

Now, “I feel like I’ve finally gotten to the place where I can balance being a mom and working,” she continued. “I’ve always done both, obviously, but it used to be where I would work a lot more. And so I’ve really shifted my focus.”

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A source told PEOPLE last month that Kourtney was “happy to be filming less for both herself and the kids.”

“As Kourtney and Scott’s kids get older, especially Kourtney feels that public exposure is not really beneficial for the kids,” said the source, adding, “She feels more and more protective of them.”

Keeping Up with the Kardashians airs Thursdays (8 p.m. ET) on E!