Rob Kardashian defends bashing ex Rita Ora on Twitter

Two months after Rob Kardashian accused Rita Ora of cheating on him with "nearly 20 dudes" via a series of now-deleted Twitter post, the E! reality star defended his actions during the Feb. 17 episode of "Kourtney & Kim Take Miami."

"Rob just got out of a really weird relationship. They were actually together for about a year but Rob was never allowed to admit that they were actually an item," his sister, Khloe Kardashian-Odom, said of his relationship with the 22-year-old British pop star. "Because she's in the entertainment industry, she wanted to present herself to the world as a single girl."

The 28-year-old "X Factor" co-host added, "I think Rob got really depressed through this relationship."

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Despite his sisters urging him to stop bashing the "Radioactive" singer online, Rob defended his actions. "I posted what I posted to keep myself from taking her back. Every time she messed up, I took her back for over a year now," he explained. "I just had to do that to make her hate me."

Kourtney Kardashian worried his actions would make him look like the villain in the relationship. "She's the one who's in the wrong but she'll probably try to make it like you're in the wrong for posting it," she told Rob.

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"It's getting so ugly," Kourtney, 33, said in a confessional. "Instead of dealing with it privately, it's just becoming a public matter now."

Rob -- who said he gained 40 pounds while dating Ora -- did have at least one concern about his Twitter tirade: "I don't want people to think I'm being a bitch," he admitted.

VIDEO: How Rita Ora cheated on Robert Kardashian with Jonah Hill

His older sister, Kim Kardashian, tried repeatedly to calm him down. "There's just no point [in tweeting]. You loved her for a reason. You aren't together for a reason now," the 32-year-old reminded him. "You just always have to take the high road."

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