The Ghostbusters star penned a touching essay for Empire Magazine's upcoming farewell issue in memory of the Star Wars icon, where he candidly recounted Fisher's role in his life.
"While filming Blues Brothers, Carrie and I fell in love and during the shoot she moved in with me into a penthouse suite in the futuristic, aluminum-clad Astro Tower, which I knew to apologize for. Carrie had the most refined eye for art and design," Aykroyd shares.
The pair, who met while Aykroyd and fellow Blues Brothers star John Belushi were castmembers on Saturday Night Live, lived together for some time in 1980, and they even thought about marriage, going so far as to get "blood tests for compatibility."
"Contemplating marriage, I gave Carrie a sapphire ring," the 64-year-old actor recalls. "Subsequently in the romance she gave me a Donald Roller Wilson oil painting of a monkey in a blue dress next to a tiny floating pencil, which I kept for years until it began to frighten my children."
While their relationship "was soaring on laugh-filled exhilaration and a vibrant, wholly satisfying physical intimacy," the couple went on a luxurious vacation to casino mogul William Harrah's legendary Lake Tahoe estate.
Aykroyd said that after he obtained some high-grade hallucinogenic drugs, "we flew up to Reno, rented a wagon and checked in for three days of full-on weeping to Christmas classics. Certainly one of the planet's greatest occasions where LSD was a factor."
Aykroyd says their relationship came to an end after moving into their new home, bought by Judy Belushi. The home, although designed by famed architect Hideo Sasaki, was a "fixer-upper."
"Carrie said, 'It looks like it was abandoned by Fred and Wilma Flintstone.' The next morning she asked me to drive her to the airport and she flew to New York," the star recalls.
"Architectural reservations notwithstanding, Carrie wasn't shallow, we had a great time," he adds. "She was also in love with Paul Simon. She married him but I hope she kept my ring."
Fisher called things off with Aykroyd in 1980, and got back together with Simon, whom she'd dated before her relationship with her Blues Brothers co-star. Simon and Fisher tied the knot in August 1983 and divorced less than a year later in July 1984. Fisher later dated talent agent Bryan Lorde, with whom she welcomed daughter Billie Lourd in 1992.
Aykroyd tied the knot in 1983 with current wife Donna Dixon. Together, they share three daughters, Danielle, 27, Belle, 23, and Stella, 18.
Fisher died late last month, days after going into cardiac arrest during a flight from London to Los Angeles International Airport. Fisher's mother, Debbie Reynolds, died after suffering a stroke the following day. For more on the actresses' lives and legacies, watch the video below.
Empire Magazine's March issue hits newsstands on Thursday.