Wednesday (April 22) would have been Glen Campbell's 84th birthday, and the country icon's widow, Kim Campbell, is celebrating his birth with the announcement of a new book. Gentle on My Mind: In Sickness and in Health With Glen Campbell, Kim's memoir about the pair's relationship, is due out later this year.

The tome will cover never-before-told details of Kim's rollercoaster 34-year marriage to the music legend, according to a press release. That includes tales of Glen's personal battles, as well as his music industry run-ins with fellow stars such as Alan Jackson, Waylon Jennings, Mick Fleetwood and more.

"As I celebrate Glen's birthday today, my mind is flooded with memories of our 35 years together," Kim tells People magazine in a statement. "To the world, Glen was a star of TV and film a legendary singer and guitarist. … To me, Glen was my husband, my best friend, and the father of our three children."

"Armed with a sense of humor and strengthened by our faith in God, we weathered the storms of Glen's battles with alcoholism, drug addiction, and ultimately Alzheimer's," she continues. "To celebrate our remarkable life together I am sharing our incredible love story in my new book."

The country singer married Kim (née Woollen) in 1982 after the pair met on a blind date the year prior. Glen's fourth marriage, Kim was 22 years his junior. The musician revealed he had Alzheimer's disease in 2011. The pair remained together until the performer's death in August 2017 at the age of 81.

Last year, Kim reflected on her husband's death. "It’s such a long, long goodbye that you’re conditioned already to accept it," she said, "But you carry around the sadness with you for so many years. The sadness lingers."

Gentle on My Mind is due June 23 from book publisher Thomas Nelson. Pre-order it here.

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