"It was very difficult for her to find out about Tristan and Jordyn — but this is what made her realize that Tristan would never change," a source tells PEOPLE

When news about Tristan Thompson and Jordyn Woods‘ tryst broke earlier this year, his relationship with Khloé Kardashian was already on the rocks, according to a source.

“When the Jordyn drama happened, Khloé and Tristan were not in a proper relationship,” a source tells PEOPLE. “They had not been for weeks. They didn’t even spend Valentine’s Day together, which was right before he messed around with Jordyn.”

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While the scandal was heartbreaking for Kardashian — who shares 14-month-old daughter True with Thompson — to learn about, she was still hopeful of reconciling with the 28-year-old NBA star.

“But this doesn’t mean that it was completely over for Khloé. It was very difficult for her to find out about Tristan and Jordyn. But this is what made her realize that Tristan would never change,” says the source. “It was heartbreaking for her.”

For Kardashian, “she always hoped there was a way things could work out, because that’s what she wanted for True,” the source explains. “She wanted True to live with both her parents.”

Reports of Woods and Thompson’s scandal first surfaced in February. On March 1, Woods shared her side of the story in a tell-all interview with Jada Pinkett Smith on Facebook Watch’s Red Table Talk, claiming that Thompson kissed her at an afterparty at his house on Feb. 17 after a long night of drinking. She adamantly denied having sex with him. Woods has since moved out of Kylie’s house and remains estranged from the family.

After finding out about the betrayal, the source says that the Keeping Up with the Kardashians star not only suffered emotionally, but the heartbreak also took a physical toll on her.

Image zoom Jamie McCarthy/Getty; George Pimentel/Getty; Mike Marsland/WireImage

“She was very stressed out and angry with Tristan. It made her physically ill. She was not in a good place,” says the source.

Ultimately, Kardashian made the difficult decision to break things off with Thompson. “Instead of her going back and forth with Tristan, she made a decision for herself that she needed to never go back to him,” says the source.

According to an insider, “Tristan was doing everything he could after to get Khloé back.”

But despite his apologies, Kardashian chose to move on for good. “He did ask her at one point to reconsider, but Khloé was too angry and disappointed with him,” says the source.

In the months since their split, Kardashian has been focused on her own well-being and raising her baby girl.

Although Kardashian and Thompson reunited to celebrate True’s first birthday in April, the mother of one has no intention of ever getting back together with the Cleveland Cavaliers player.

Image zoom Tristan Thompson and True

“Now, she would never go back with Tristan,” says the source. “She knows that he will never change.”

While the Revenge Body star isn’t interested in romantically being involved with Thompson in the future, she isn’t using any pain from her past to negatively impact his relationship with True.

Image zoom Khloe Kardashian and True

In March, Kardashian came to Thompson’s defense after multiple sources said that he wasn’t spending enough time with their daughter.

Responding to a fan who tweeted that all True “needs is her mom,” Kardashian called Thompson a “good dad.”