The country star developed dysphonia, a vocal cord disorder often caused by stress, following her 2008 separation from producer Robert 'Mutt' Lange, and was not able to sing for several years.
The "Man! I Feel Like a Woman" star was also subsequently diagnosed with Lyme disease, and feared she wouldn't perform again because of the ailment.
However, she praises Lionel for convincing her to duet with him on their 2011 collaboration "Endless Love".
"He's such a wonderful man, I'm so blessed to have met him," she told U.S. chat show "The Talk". "The Lyme disease battle is just an ongoing thing. Once you've had effects from Lyme disease, in my case they're permanent. So I really struggle with the damage to my vocal cords. It'll be an ongoing therapy for the rest of my life. I felt like that was it for my singing career, that I'd never sing again, let alone record again."
Shania was initially going to turn down Lionel, but after speaking with him on the phone, she knew she couldn't resist singing with the soul icon.
"Lionel called my managers up and said, 'I need to speak to her, I want to do this duet with her on my album. She can pick any song she wants,' " she continued. "I just kept saying, 'No.' Not to say no for the sake of turning down Lionel Richie, because of course I'm going to always jump at that chance. I was too afraid, I really believed I couldn't do it and I didn't want to embarrass myself in front of Lionel Richie. I didn't want to try and then fail..."
"He insisted, (and) my husband (Frederic Thiebaud) said, 'Look at least turn him down yourself,' and I said, 'You're right, of course I owe him that,' " Shania recalled. "So I got on the phone with him with the intention to say, 'No, I can't do it,' and he convinced me. He just has such a great heart and it comes out through his messaging and his whole psyche and I was convinced."