“Same Old Love” singer Selena Gomez cannot believe her ex-boyfriend, Justin Bieber, and “Keeping Up With the Kardashians” star Kourtney Kardashian are supposedly dating, Hollywood Life wrote in an exclusive report Thursday. Kardashian is 15 years older than Bieber, who was rumored to have dated her younger sister, Kendall Jenner.

“Selena’s just as shocked as everyone else over this,” an insider told Hollywood Life. “She’s known Kourtney for years and never would have pictured her and Justin together.”

But she’s not the only ex who is shocked by the tryst. Scott Disick, the father of Kardashian’s three children and her on-again, off-again boyfriend of eight years, is also said to be stunned. "He is convinced Kourt is doing it to hurt him. And she succeeded,” an insider told People magazine Thursday. "Of course it stings a bit that Kourt is hooking up with Bieber. But Scott also knows his place and that he doesn't have the right to have a fit about it.”

Even though he’s hurt by Kardashian’s new relationship, Disick is focusing on himself these days. He’s struggled with maintaining sobriety, but wants to kick his addiction for good. “It's no problem for him to be out with friends and not drink," the source added. "He feels great not drinking. He loves spending time with his kids." 

There might not be much for Disick, a self-proclaimed "Lord," to worry about, though. Kardashian and the young pop stars aren’t serious, sources say. “They’ve been hanging out and messing around,” an insider told Us Weekly, according to Hollywood Life. “I don’t see it becoming anything serious because the difference in age is too great and Justin likes being single, but they are having fun together.”

Even though multiple news outlets have written about the supposed affair, neither Kardashian, 35, nor Bieber, 21, have confirmed the rumors.

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