AFP PHOTO/VALERIE MACON/AFP/Getty
10/29/2008 AT 09:50 AM EDT
After enduring months of agonizing treatment
for hepatitis C, Natalie Cole says, "It feels great to be back!"
"I feel sturdy and strong," the 58-year-old Grammy-winner told PEOPLE Tuesday at a CD signing for her new album, Still Unforgettable
, in L.A.
And while the singer is virus negative
, Cole is now battling kidney problems, and must undergo dialysis three times a week, three hours a day.
"The dialysis is to wash my blood, to keep my kidneys functioning," she explained. "When they put me in the hospital, [my kidneys were] only about 8 percent [functioning]."
But through all the tests and treatments, Cole is still driven to make music.
"And my voice is still here! It's almost like a miracle because [the treatment] didn't affect my [singing]."
Cole, who was hospitalized in September
after suffering a setback in her treatment, described battling the liver disease as her "biggest challenge" ever.
"I've never been through anything like this," she said. "I've never been this ill."
But, she explains, "I love what I do so much. I just keep going. Not much can bring me down."
1978: Natalie loves three men at once RELATED GALLERY:
Read about other stars battling illnesses