Dion sat down with People for its cover story
to talk about her life since she lost both husband René Angélil and brother Daniel Dion to cancer.
The singer is scheduled to receive the Icon Award and perform at Sunday night's Billboard Awards. She will be singing a cover of Queen's "The Show Must Go On," at the awards and told People "René always insisted the show must go on."
"You know what, I'm 48 years old and I lost the love of my life," she said. "I miss him a lot from when he was great but not when he was suffering. I cannot be selfish. You have to let people go. I feel at peace."
Dion said she is trying to be strong for her three children with Angélil, René-Charles, 15, and 5 year-old twins Nelson and Eddy.
The children were not present during her husband's final moments, she told People.
"I got on my knees and I kissed him," Dion said. "It was the coldest thing I've ever experienced in my life, but it was amazing. I said, 'Promise me not to worry. I'm fine, the kids are great, we're gonna be okay. It's enough suffering. Just go in peace.' "
The couple first met when Dion was an aspiring 12-year-old singer and the much older Angélil became her manager. They were married for 21 years.