Actress Marlo Thomas has paid tribute to her late husband, talk show legend Phil Donahue. Donahue died Sunday at 88 following a long illness, his family confirmed to “Today” Monday.

The Emmy-winning former host of “The Phil Donahue Show” passed away at home surrounded by his loved ones, including his wife of 44 years, his sister, his children, grandchildren and his golden retriever, Charlie.

On Monday, Thomas, 86, who is best known for starring in the ‘60s and ‘70s sitcom “That Girl,” posted a lengthy tribute on Instagram with a photo of the couple riding a scooter when they were younger. “I’m sure by now you’ve heard the very sad news that I lost my sweetheart last night,” she began.

Thomas, who played Jennifer Aniston’s mom, Sandra Green, in “Friends,” continued, “I know you understand that I’ll be stepping away from this page for a while to take care of myself and the many people who took care of Phil, and held him close to their hearts.”

Donahue’s talk show aired for 28 years, from 1968 to 1996.

While broadcasting from 30 Rockefeller Plaza, Donahue welcomed major guests on his show, such as Muhammad Ali, Whoopi Goldberg, Billy Crystal, Steve Martin and Jamie Lee Curtis.

Donahue was the first person to interview Nelson Mandela following the South African president’s release from prison in 1990. He was also the first American talk show host to tape from the Soviet Union.

Thomas appeared as a guest on his show in 1977 and they married in 1980.

“It was kind of love at first sight,” Thomas recalled on “Late Night with Seth Meyers” in 2021. “Something chemical happened.”

Donahue had five kids from a previous marriage. He did not have children with Thomas.

In the couple’s 2020 book, “What Makes a Marriage Last: 40 Celebrated Couples Share with Us the Secrets to a Happy Life,” Thomas wrote, “Had Phil and I been younger, we might have been more impatient and missed each other. But being older — me in my late 30s, Phil in his early 40s — we trusted our hearts and made the effort.”

Thomas added in her lengthy Instagram caption that she didn’t want to “disappear” from social media without thanking the public “for the beautiful messages of love and support that have been coming in all day, and for the wonderful and generous way that you’ve let Phil and me share our life adventure with you over the years.”

She went on to thank all of the couple’s Instagram followers.

“As a man who spent his career loving his audiences, Phil got such a kick out of our cozy little community here, and I know he would be very touched by the heartwarming thoughts and memories you’ve been sharing,” she wrote.

She ended her message saying that until she “returns,” she wishes everyone “good health and happy days in the company of family and friends, and I hope that you will continue to hold close those you cherish most, just as I was blessed to do with my beloved Phillip.”

Thomas signed off, “Love, Marlo.” She also explained that the photo of the couple on the scooter she had posted “is one of my favorite photos of Phil and me, taken on vacation.”