The former couple announced their split last July after nine years together and Scott, who has battled with an alcohol addiction, initially struggled with the breakdown of the relationship and checked himself into rehab shortly after they went their separate ways.
Although he successfully completed his stint at the end of last year, Kourtney, 36, is said to be convinced he'll relapse.
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A source explained to Us Magazine: "Kourtney's always known there's a possibility he would go back to what he is and revert to bad behaviour."
And he certainly raised eyebrows about a possible relapse over the festive period when he stepped out in Los Angeles with a black eye after he reportedly fell over.
Scott sought hospital treatment for the cut the day before Christmas but it's not known how the fall occurred or whether he was under the influence of alcohol at the time.
-Bang! Showbiz
