Kourtney Kardashian says Scott Disick's 'subtance abuse' was deal-breaker

The Keeping Up With the Kardashians reunion special is certain to raise eyebrows as they speak about topics that were off limits on the show.

Hosted by Andy Cohen, the Kardashian-Jenner clan will be grilled on a range of topics which includes Kourtney Kardashian and Scott Disick’s breakup, Khloe Kardashian’s opinion of the Tristan Thompson cheating scandal as well as Kris Jenner and ex Caitlyn Jenner’s rocky relationship.

In the sneak peak it showed Kourtney speaking about her relationship with Scott and shared what was the breaking point for her.

"Do you think your relationship might have turned out differently if you hadn't shared so much of it?" the host asks.

While she agreed with the host's question the Poosh founder pointed out how her ex, whom she shares three children with, formed a habit with misusing alcohol, causing their eventual breakup.  

"Probably, but I think the substance abuse was the deal-breaker," says Kourtney said, referring to her ex’s alcohol abuse.

"I was pretty irresponsible," Scott admits.