Khloe Kardashian and Kris Jenner are not the only Keeping Up With The Kardashians stars rumored to have relationship troubles.

Kendall Jenner reportedly broke up with her high school sweetheart, college football player Julian Brooks. An insider cited in the latest issue of Star said the reality star feared he was cheating on her because he would be unavailable for several days at a time.

"He would disappear for days and not answer Kendall's text messages," a source said.

The friend said she ended their relationship because "she couldn't live with the doubt" of wondering if he was cheating or not.

The former couple both attended Sierra Canyon School and began dating in May 2012, according to the report. Their relationship went public after Kendall tweeted Brooks in May, "Can't believe it's been a whole year." He later professed his plans to be with her for the long run when he tweeted a friend, "@CALGANGJC: Mm. Kendall Kardashian is going to be my Future GF... Maybe wife haha." 

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Enstars reported on Aug. 15 that Kendall wrote a series of cryptic tweets suggesting she ended things with the College of Nevada football player. Kendall re-tweeted a friend's statement on Aug. 15 that read, "The only good man I've met in my life is my dad." Julian then re-tweeted her second note that day: "Don't who to trust or where to go anymore."

The reality star then followed up with another re-tweeted message: "A jealous girlfriend is a faithful girlfriend. If she doesn't get jealous when someone has your attention, it's because someone has hers."

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At the time, Brooks tweeted several messages hinting at their relationship status. He re-tweeted a friend's message saying, "This whole night just went to s--t in EVERY way possible," he wrote "thats what happens when people start being fake" and later, "loyalty and truth is all l need."

He wrote on Aug. 16 "never appreciated" and "When youre going through hell, keep going."

On Aug, 17 Kendall wrote, "this time won't you save me?" though she did not directly address anyone.

Kendall attended her sister Kylie Jenner's lavish Sweet 16 birthday party that night and Brooks was not in attendance. The next day he wrote on Twitter, "gotta let it  go, gotta let it burn." They were last seen together hanging at Bruce Jenner's Malibu vacation home during the Fourth of July weekend. 

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