Kourtney Kardashian
Kourtney Kardashian attends the Brian Bowen Smith WILDLIFE show hosted by Casamigos Tequila at De Re Gallery in West Hollywood, California, Oct. 23, 2014. Getty Images/De Re Gallery/Jason Merritt

After being dissed by singer Justin Bieber during a recent radio interview, Kourtney Kardashian is regretting ever getting involved with the 21-year-old singer, Hollywood Life reported. Dating rumors about the “Sorry” singer and Kardashian emerged last month and were even claimed to be true by gossip debunking website Gossip Cop.

“Kourtney wants a major explanation and apology. She’s not the one who leaked their romance to the public. She feels like she’s being punished and it just goes to prove her initial instinct — that Justin is too young and too immature for her. She’s kind of beating herself up for ever getting involved with him in the first place, and not listening to her gut. She really regrets the whole thing,” a source told Hollywood Life.

The report comes after Bieber was asked on the "Bert Show" about his relationship with Kardashian, to which he replied, “I’m being used, man. What can I say?!”

The Hollywood Life report also said that the “Keeping Up With the Kardashians” star feels that she has been “stabbed in the back” after the comment.

The source reportedly said: “She has been nothing but respectful towards him and their relationship. She has been so protective of him and now she feels completely stabbed in the back.”

Bieber is currently dating model Hailey Baldwin and was seen getting close to her. Meanwhile, Kardashian has been spotted repeatedly with her former partner Scott Disick, with whom she has three children, over the last few days.

A report by TMZ on Wednesday said that Disick bought a house close to the Kardashians for $5.96 million. The report added that he made the move mainly to get help from the Kardashians to stay sober for the sake of his children.