Fellow singer Janet said the family tried to help Jacko battle his addiction to prescription drugs.
She told a US telly show how hard it had been to accept the star’s death and demanded Conrad Murray be banned from practising medicine forever.
Janet, 43, said: “He (Murray) was the one that was administering. I think he’s responsible.”
The Jackson family knew of Michael’s addiction problems and they had tried to intervene.
Janet, said: “Of course, that’s what you do. Those are the things that you do when you love someone. You can’t just let them continue on that way.
“It’s been a tough year. You have your days where it’s just really hard to believe. And a day doesn’t go by that I don’t think about him.”
Officials say Dr Murray, 56, gave Jacko, who was 50, a lethal dose of the anaesthetic propofol on June 25.
Janet added: “It just didn’t ring true to me. It felt like a dream. It’s still so difficult for me. You have to move on with your life. You have to accept what is and I understand that.”
She last saw Michael two days before her birthday in May. She added: “We had a lot of fun, laughing.
“I was being loud and he thought it was so funny.”
She added that the LA memorial service for Michael in July helped her come to terms with his death.