In a new interview with ABC's Robin Roberts, the pop star reveals that she (and her family) staged a drug intervention on more than one occasion.
"Of course, that's what you do," she says. "Those are the things that you do when you love someone. You can't just let them continue on that way. And we did a few times. We weren't very successful."
Was Michael in denial? "Possibly," says the singer, 43.
She adds, "I wish he could answer this question for you and not me. I felt that he was in denial."
As for Michael's reaction to the family, she says he understood that their motives were "out of love," but adds, "You can't make 'em drink the water. I'm a true believer in prayer, a big believer in prayer – but it's, it's something that you can't do for them. Something they have to do for themselves."
In the interview, the singer also makes no qualms about who she believes is responsible for Michael's death in June.
"I think [Dr. Conrad Murray] is responsible. He was the one administering," she says, referring to Michael's personal physician. Murray was with Michael the morning he died, and has admitted giving the singer the powerful anesthetic propofol.
Roberts's In the Spotlight with Janet Jackson airs Wednesday at 10 p.m. on ABC.