Kourtney Kardashian Explains Her Marriage Hesitance: 'I Have Major Commitment Problems'

Access Hollywood
Kourtney Kardashian and Scott Disick celebrate New Year's Eve at the Sugar Factory American Brasserie at the Paris Las Vegas on December 31, 2011 -- WireImage

With their second child set to arrive any day now, Kourtney Kardashian and longtime beau Scott Disick have puzzled many fans with their decision to remain unmarried - an issue Kourtney addressed during an appearance on "Jimmy Kimmel Live!" on Thursday.

"I have realized that I have major commitment problems during this pregnancy," Kourtney - who sat between sisters Khloe and Kim - told Jimmy, when asked why she and Scott have hesitated to head down the aisle. "I'm really claustrophobic and all my issues - I have a lot of them - but they all stem from this thing, like, I can't commit to anything."

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The 33-year-old reality mom was quick to add that her fear of commitment is not due to questioning her love for Scott.

"I love Scott and he is my partner, we're committed to each other, we're together, we have a great relationship," Kourtney said. "So that's not what it is."

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"I wish I would've learned from you earlier," Kim added, mocking her whirlwind romance with Kris Humphries, which resulted in a 72-day marriage to the basketball star.

"Why don't you try it for a little while like Kim did?" Jimmy jokingly asked Kourtney.

With the London Olympics just around the corner, Jimmy asked the girls if they were able to comprehend the magnitude of stepdad Bruce Jenner's athletic achievements (he took home the gold in for decathlon at the 1976 Montreal games).

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Kourtney, who used to think Bruce was "a swimmer," said she didn't fully grasp the scope of Bruce's Olympic accomplishments until the family attended the games in 1996.

"I remember we went to the decathlon and that was the first time I really had such a respect for Bruce and for what he did because I was like, 'Oh, you're not a swimmer, you did these 10 events!'" she said. "I never knew what he did."

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While the sisters respect Bruce's feat, they agreed they've heard enough Olympic stories to keep them going for a while, and said they warn their beaus to steer clear of sports talk with their stepdad.

"I told Kanye, 'Whatever you do, don't ask him any political questions, don't ask him about sports, Olympics, nothing, unless you want to sit for hours and hours and hours,'" Kim told Jimmy.

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