Glenn Frey‘s death on Monday (Jan. 18) stunned the music world, but according to the Eagles member's good friend, fellow artist Bob Seger, Frey's health was much worse than fans knew.

In late 2015, Frey, who turned 67 in November, underwent “major surgery” due to his long-standing intestinal issues, which he believed to be a result of his early band days involving drugs and alcohol and which he had been battling since the early 1980s. Seger tells the Detroit Free Press that he received word from Don Henley in November that Frey was at the Columbia University Medical Center in New York City, suffering from a bout of pneumonia, as well as complications from rheumatoid arthritis and acute ulcerative colitis.

"He was in a coma, and he'd come out, but then he couldn't breathe. They'd put him back into the coma," Seger recounts. "They were trying like hell to keep him alive ... [Eagles manager] Irving [Azoff] pulled every ace out of the hole — he had the eight best specialists working on Glenn."

Sadly, Seger says, "About a month ago, they had to throw up their hands."

Seger and Frey last saw each other in July, at an Eagles concert in Detroit, Mich. The Eagles guitarist had flown in last-minute from Los Angeles, from one of his children's graduations.

"He was in a great mood. His voice sounded great," Seger remembers. "[The song] "Saturday Night" — when you hear that harmony, it’s still mind-boggling how truly wonderful it is. And he created that."

Seger adds, "He loved his family. He loved those kids. He was devoted to them. He was so much more than people knew he was ... He would never fail to start with telling me how grateful he was that audiences were still there. He loved the band. He loved the fact he could keep doing this. And he kept doing this until six months before he died."

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