"I realize I'm in the wrong. I've been in the wrong a long time," Disick said.
Disick and Kourtney had dated for nine years before splitting up in 2015.
The 32-year-old father of three also revealed that since his split with Kourtney, he's "never been this unhappy in [his] life, and admitted that their kids, Mason, 6, Penelope, 3, and Reign, 1, are the only thing that's keeping him going right now.
"If I didn't have those kids, I would kill myself," Disick said. "But I have them and I'm going to be here and I'm going to make it right for them. I just hope that somehow, God can like, give me a chance or us a chance at this. It's weird to lose that many people that quick, you know."
Jenner, who showed support for Disick on social media after his split from Kourtney, reminded him that despite everything they've been through, the Kardashian family still loves Disick, and urged Disick to keep working on becoming the man he wants to be.
"People are human and they make mistakes," Jenner said. "You have to make the decision that what you want is to be a partner and a dad and involved and present and committed and you fight for what you want and you need and you love."