As Life & Style exclusively reported, Kourtney Kardashian has decided to marry much-younger boyfriend Younes Bendjima — and baby daddy Scott Disick is understandably livid. Sources say the father-of-three “went ballistic” when he heard there would be a wedding.

An insider tells Life & Style that the 34-year-old angrily called his ex “over 30 times” to talk, but she refused to answer. “Those close to Scott are concerned his partying will spiral even more out of control now,” the insider shares. “He never thought Kourtney would move on from him, but now he knows he was wrong.”

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Despite hooking up with countless women over the past few months, the notorious partier “keeps texting, promising he’ll change,” the insider adds. “But Kourtney is done with him.” The fact that the brunette beauty is willing to walk down the aisle with Younes after such a short amount of time is particularly hurtful to Scott. He revealed on an episode of KUWTK earlier this year that he had previously proposed to Kourt with a ring.

“It was really weird. I don’t think we told anybody actually,” he recalled. “It was somewhat cute and then we just got scared about like media and this and that. And we were like, ‘Let’s just put the ring aside and we’ll talk about it another day.’ Never spoke about it again.”

A different source told Life & Style in May that Scott has tried numerous times to keep Kourtney away from Younes. “Scott will do anything to sabotage Kourtney’s relationship, including showing up wherever Kourtney and Younes are hanging out together,” the source said. “He’s also been asking around, trying to get some dirt on Younes so he can bring it back to Kourt and persuade her to dump him.”

For more details about Kourtney’s upcoming nuptials, pick up the latest issue of Life & Style, on newsstands now!