According to TMZ, Bendjima went off on another vacation shortly after the pair returned from the month-long European vacation and she claims that's when the model cheated, leading her to end the nearly two-year relationship.
Kourtney has so-far not commented publicly on the breakup, after news broke yesterday.
The sources goes on to say that eventually Kourtney Kardashian found out that Younes Bendjima was "running around on her", and even though she "knew it", but continued "denying it", until she couldn't deny it any longer.
"You never know the private struggles someone could be going through and how awful it may be making them feel", she wrote.
Meantime, Bendjima - described as a model and former boxer - took to his Instagram story to blast media speculation about his split, according to Page Six. "I'm not attached to this "life" so you can't touch me ..."More news: Powerful Hurricane Hector on the horizon
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"They really want me to be the bad guy", he wrote over a screenshot of the Daily Mail's report alleging Bendjima was rebounding with a "bikini-clad" woman.
The couple was together for almost two years, meeting first at Paris Fashion Week in 2016.
Kourtney reportedly dumped Younes but now, Kim and Khloé are out for blood!
Ozuna adds that the Mexico trip was for a mutual friend's birthday and that the two of them were celebrating with a group of 13 people. "Although he is happy in his relationship with Sofia, he never liked Younes for Kourtney", a source told E!. "Fuck your Hollywood bullshit (cant have fun with your friends no more)." . News that they are not "romantically involved in any way, shape or form".
This article has been edited and republished from the New York Post with permission.