The star – and dear friend to the late singer – took to her Twitter account to confirm that she would not go to the Los Angeles event despite being asked to participate.
"I've been asked to speak at the Staples Center," she wrote Monday. "I cannot be part of the public whoopla. And I cannot guarantee that I would be coherent to say a word."
The actress, 77, wrote that she believes Jackson would not have wanted her to share her sorrow in public.
"I just don't believe that Michael would want me to share my grief with millions of others. How I feel is between us," she posted. "Not a public event."
A moment later, she added: "I said I wouldn't go to the Staples Center, and I certainly don't want to become a part of it. I love him too much."