KUWTK : Scott Disick Tells Kourtney Kardashian He Doesn't 'Like Seeing' Her 'with Another Guy'

Scott Disick is getting real about his complicated relationship with ex Kourtney Kardashian.

In a sneak peek at Thursday's episode of Keeping Up with the Kardashians, Scott, 37, accuses Kourtney, 42, of flirting with a lifeguard.

"I feel like it annoys me, like, when you flirt with this lifeguard," Scott says, to which Kourtney replies, "I'm definitely not flirting with the lifeguard."

The Talentless founder notes that "maybe it's just in my head" while reiterating how seeing her around another man "bothers" him.

Scott continues to claim that Kourtney's "a little flirty," which she promptly denies again. He then suggests that his own "insecurity" is likely at play.

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"I feel like, I just don't like seeing you with another guy," he says to the mother of his three children. "It hurt [sic] me when you're with somebody else and waking up to, like, looking at pictures of you with this guy you were dating. It was just unhealthy and it just made me upset and sad, you know what I mean? And now, I wake up with no real problems. I'm, like, care-free in the sense I don't have that, which used to take up a lot of space in my mind all day."

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The Flip it Like Disick star adds: "The big fear is if you start dating again, then it goes back to that and I have to feel, like, a different way again and it's just hard. It sucks. I guess now that you're single and I'm single and you haven't been with somebody in a bit, either we figure out creating our own lives together or separately."

Scott continues to address the challenges of the pair's current, close-knit dynamic after their split in a confessional session.

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"It's definitely that Kourtney and I basically spend 90 percent of our lives together, travel together, do everything together, see each other every day and, you know, the only difference is at the end of the night we kind of part ways and go and sleep in separate houses," he says. "This whole limbo state isn't that cool anymore and I surely don't want us both to wake up and be 50 years old and doing the same thing."

Kourtney has been linked to Travis Barker since January, while Scott has been dating Amelia Gray Hamlin since last October.

The exes split in 2015 after dating on and off for nine years. Together, Kourtney and Scott co-parent sons Mason, 11, and Reign, 6, and daughter Penelope, 8.

Kourtney Kardashian/Instagram Scott Disick and Kourtney Kardashian with their kids

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The former couple's relationship has been addressed throughout KUWTK's 20th and final season, which began airing last month. Earlier this season, they enjoyed a solo movie night together and joked about their past sex life. Scott also claimed during the premiere that his former girlfriend Sofia Richie gave him an "ultimatum" to choose between her and Kourtney ahead of their August 2020 split.

"I thought I would give it a try and make her more of a priority, but then even when doing that, I feel like she just started wanting to push Kourtney out," he told Kim Kardashian and Khloé Kardashian. "And I said like, that's the most important thing to me is my kids and that's my family, and the only family I have, including you guys along with it. She was like, 'I don't want to share you as a boyfriend with Kourtney.'"

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