“In his ideal world, he would still be with Kourtney,” the source tells PEOPLE exclusively. “He wants her back, but he just isn’t taking the steps needed to make that happen.”
While Disick is still spending time with their kids — Mason, 7, Penelope, 5, and Reign, 2 — his relationship with Kardashian “is pretty fractured right now,” says the source. “Scott is really sad about it, and it’s part of why he’s lashing out.”
Over the weekend, the self-proclaimed Lord, 34, headed to Las Vegas and partied throughout the day and well into the night. He sipped on vodka and beer and was seen chatting it up with several women at his VIP table.
“He’s in a partying mindset, and Kourtney is obviously not happy with that,” says the source.
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The mom of three, 38, is also having her own fun, however. The Keeping Up with the Kardashians star is still seeing 23-year-old model Younes Bendjima, but is keeping things casual.
Says the source, “Everyone around her knows she’s just having fun and no one expects it to turn into anything serious.”