The party-loving reality star was dumped by Kourtney over the summer after she allegedly grew tired of his wild ways, which included getting cosy with another woman while he was abroad and Kourtney was home in LA with the kids.
She pulled the plug on their nine-year relationship in July.
According to US Weekly, following a recent stay in rehab, Scott is now trying to make amends with people he has hurt, including Kourtney.
A source said: "[He] has apologised to everyone. It's part of his treatment. He's also been going to the rehab centre every day and spending a lot of time with his sober companion. He is really committed to this."
Scott was visited by Kourtney and their kids - Mason, five, Penelope, three, and Reign, 11 months - and Kourtney's mum Kris Jenner while he was at rehab.
This week, Kourtney's sister Kim Kardashian West said the whole family is behind him, telling People: "Every time we [see him], he's back to his old self and he's so happy. But it's an adjustment. I don't want to say anything too soon."
Keeping Up With The Kardashians airs Sunday nights on E!
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