"She [Courtney] was the first person to give my son Jack the prescription drug OxyContin. There's not a shadow of a doubt about that. My dislike towards her is very personal,' the Daily Mail quoted Osbourne, as saying.
"I'm not saying Jack wouldn't have taken it if she hadn't given it to him, but I'm appalled that an adult mother would give that to a 15-year-old boy.
"How could she do that to someone else's child? I haven't had a row with her, but I will never talk to her."
Now, Love has hit back at the X Factor judge saying that she can never give drugs to a teenager.
"I never did that. I would never give drugs to a teenager. F*** you Sharon - as if I would ever give drugs to a teenager,' Love said.
The 42-year-old also said that she saw the drug for the first time when she met Jack. "It was the first time I was ever introduced to them (OxyContin)," she added.
Jack was addicted to drugs and alcohol in his teens, but he successfully overcame them.
He has written about kicking his habit in his autobiography, '21 Years Gone'.