Khloé Kardashian has moved on since her divorce from Lamar Odom, but her ex still occupies her thoughts as he continues to seek treatment in rehab.

But it’s not his health that she’s most worried about. “Khloé knows that a lot is going to come up while he’s in group therapy, and she can’t stop thinking about what all these strangers are going to find out about her,” a source tells Life & Style.

MORE: Lamar Odom Will Document Rehab, Recovery on New Reality Show

“Khloé is happy he’s getting help, but she’s scared about what the people who are listening to his story in group therapy will say once they leave,” the source admits.

After all, Lamar “not only has all the dirt on Khloé, but he has firsthand knowledge of the Kardashian secrets that could bring the family down,” a different insider shares.

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For example, before he separated from Khloé in 2013, the former pro athlete witnessed Scott Disick’s out-of-control partying, the unraveling of Kim Kardashian’s marriage to Kris Humphries, and the lengths Kris Jenner went to for ratings.

“Khloé and her mom are already discussing how to deal with the revelations,” the insider adds. “They’re fearing the worst.”

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Lamar recently talked about his near-fatal overdose in October 2015 for the first time, revealing what happened before he was found unconscious.

“I wasn’t in a good place mentally, especially mentally, before the incident happened,” he said. “My wife at the time, we were going through some things. I was in a dark place. So, I guess they say everything happens for a reason. So, I guess the reason is I’m here and I can tell the story.”

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Lamar with good friend Kobe Bryant in April.

Lamar confessed that he didn’t know he had nearly died until Khloé told him. “I couldn’t talk,” he shared. “Nothing would come out when I would open my mouth. So I was scared.”

For more on Lamar’s recovery, pick up the latest issue of Life & Style, on newsstands now.

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