In an exclusive sneak peek at Sunday’s episode, Kardashian, 38, sits down with momager Kris Jenner after having returned from her wild birthday vacation to Mexico in April — but the conversation takes an intense turn when her ex Scott Disick is brought up.
“It was really, really the best four days of my life,” she gushes of the extravagant girls trip.
“I don’t think you should actually put on social media that you got so sick that you threw up and then went to sleep in it,” chides Jenner, 61.
“Why? It was so funny,” Kardashian says. “I feel like on social media lately everyone takes themselves so seriously, and I’m over it.”
Kardashian then asks about how Disick, 34, was doing while she was away.
“I think he was jealous,” Jenner admits. “Because you were having fun, spending time with other people.”
“Well, that’s really not fair,” Kardashian fires back. “It’s just like, I can’t even live my life. I can’t even go anywhere. He needs to get a f—ing life and leave me alone.”
“All he does is try to make everybody else feel bad for him and try to make me look like the bad guy in the situation when clearly I’m not, from 10 years of this going on,” she adds.
Jenner points out that Kardashian might be “sad” if Disick, with whom she shares three children, truly left her alone.
“You always want what you can’t have,” warns Jenner. “And when somebody is right there giving you their heart on a platter…”
“He’s not!” Kardashian interrupts. “If he was, that [would be] one thing. He’s not. Mom, that’s what he makes it seem to you, to Kim, to Khloé, to the world, to everybody. He sits there and grovels and feels bad for himself.”
“If that’s his truth, why can’t he get it together?” she continues. “I have to handle it when he’s out photographed with a different hooker every day.”
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In the two and a half years since, Disick has regularly been spotted cozying up to different women in Los Angeles, New York City and abroad — most recently with 19-year-old Sofia Richie, whom a source recently told PEOPLE is calling Disick her “boyfriend.”
Kardashian, meanwhile, has been dating 24-year-old Younes Bendjima — and in the KUWTK 10th anniversary special (which aired last month but was taped in April), she indicated that she and Disick aren’t likely to reconcile.
“I guess we’re co-parenting our kids and just trying to get along,” she said. “He’s family. But I mean, we’re definitely psychotic.”
“The debauchery that’s gone on has definitely closed the door several billion times,” she added. “He [behaves] for a time period, he can’t be consistent.”
“Here’s the thing,” Disick said. “Every time I become too good of a person, she stops loving me, because she fell in love with a person who was a little bit f—ed up. I treat you like royalty, you don’t say hello to me. I spit in your face, you’re like, ‘Hey babe.’ “
“That’s not true,” she insisted.
Disick also denied dating other people — with a wink, of course.
But according to Kardashian, she’s okay with that: “It’s not dating,” she said. “It’s just like, you know …”
Keeping Up with the Kardashians airs Sundays (9 p.m. ET) on E!