Paul Simon remembers Carrie Fisher fondly.

After the singer learned that the Star Wars actress had died at age 60 on Tuesday after going into cardiac arrest days prior, he took to Twitter to pay tribute to his ex-wife. "Yesterday was a horrible day," he wrote on Wednesday morning. "Carrie was a special, wonderful girl. It's too soon."

Fisher and Simon had an on-again, off-again relationship for over a decade and got married in 1984, only to divorce that very same year. In the 75-year-old musician's biography, Homeward Bound: The Life of Paul Simon, author Peter Ames Carlin writes that their relationship came to an end after a psychedelic trip in the Amazon.

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“Once they saw each other, no one else mattered to either of them,” Carlin recalls in an excerpt of the book obtained by People . "Carrie added velocity to [Paul’s] life, a kind of wild energy that often set him alight and sometimes made him scream."

Carlin adds in the biography that the two did fight "a lot" and Fisher's recreational drug use at the time became a problem in their relationship. “There had always been something perfect about them when they were getting along: the way they huddled together, the way he grounded her, the way she could make him laugh so easily,” Carlin writes of their romance. “And he loved her, with a desperation that could frighten him.”

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Simon wasn't the only former flame of Fisher's to pay tribute to her. Her Star Wars co-star, Harrison Ford, whom she recently claimed to have had an affair with, also remembered the actress. "Carrie was one-of-a-kind... brilliant, original. Funny and emotionally fearless," he said in a statement to ET. "She lived her life, bravely... My thoughts are with her daughter, Billie [Lourd], her mother, Debbie [Reynolds], her brother, Todd [Fisher], and her many friends. We will all miss her."

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