"I am devastated," the former Apprentice star-turned-magazine editor tells RadarOnline.com exclusively.
"He was the love of my life."
As RadarOnline.com previously reported, the Oscar-nominated actor died Monday at age 54.
Omarosa saved Duncan's life by performing CPR on him at the time of the heart attack in July but he never fully recovered and was still hospitalized at the time of his death.
Both public and private memorials are being planned, and Duncan's Hollywood friends are already expressing their grief.
"RIP Michael Clarke Duncan," tweeted Jordin Sparks. "Thank you for being so kind to me & for sharing your talent with the world. You will be truly missed."
Dule Hill wrote, "Life is so precious. A talented brother and a kind spirit. RIP Michael Clarke Duncan."
And Mario Lopez tweeted that Duncan was "One of the nicest & most professional guys I've had the pleasure of knowing. So sad…"
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