Country music legend Glen Campbell is in the final stages of Alzheimer's disease, his wife reports, and he can no longer play guitar or even sing.

Kim, his wife of 34 years, told The Tennessean Glen tries to sing but the words "are gibberish, not a melody we recognize, but you can tell it's a happy song," and the words make sense to him. "He has a song in his heart. So that brings me a lot of comfort."

She also told the paper that when he was diagnosed in 2011, doctors said "because Glen continued to do music it probably helped him plateau in the early and middle stages." It was music he turned to when he was upset over anything, she said.

Kim said music sparked the Rhinestone Cowboy's memory and helped him carry on — Glen, now 80, even embarked on a much-publicized farewell world tour extending the dates after standing-room only receptions. A documentary, "Glen Campbell: I'll Be Me," chronicles his life with the disease.

Glen and Kim moved to Nashville to be nearer to their son and daughter and a supportive music community, shortly after the diagnosis. In 2014 she made the difficult decision to move him to a full-time care facility near the couple's home in Nashville. She said that it was her husband's wish that she carry the torch for him: "Glen wants me to continue to speak out on the disease," which she does, on national tours.

"I want to let people know that there’s hope out there, there’s help out there; they don’t have to do this alone," Kim told The Tennessean. "They can’t do it alone. It will take you down."