After Cooper presented Pitt with a best supporting actor award at Wednesday's National Board of Review Annual Awards Gala, Pitt took to the stage and warmly hugged him.
"Thank you, Bradley. Bradley just put his daughter to bed and then rushed over to do this. He's a sweetheart," Pitt, 56, shared before revealing it was Cooper who helped him find the strength to give up booze.
"I got sober because of this guy. And every day's been happier ever since," said Pitt, who won the award for his performance in "Once Upon a Time in Hollywood."
The grateful actor then gave Cooper, 45, a thumbs up and gushed, "I love you, and I thank you."
(Warning: In the above video, Pitt utters an obscenity during his acceptance speech.)
Pitt quit drinking after his split from wife Angelina Jolie in early 2017. He opened up about his history of alcohol abuse during a candid interview with the New York Times last September.
"I had taken things as far as I could take it, so I removed my drinking privileges," he explained.
After Jolie filed for divorce, the actor spent the following year and a half in Alcoholics Anonymous, taking part in an all-male recovery group.
"You had all these men sitting around being open and honest in a way I have never heard," he said of the experience. "It was this safe space where there was little judgment, and therefore little judgment of yourself."
The New York Times interview wasn't the first time Pitt opened up about his history of abusing alcohol.
In 2017, he told GQ Style that throughout his early adulthood, he used marijuana and alcohol as "pacifiers" to soothe him and allow him to keep "running from feelings."
"I mean I stopped everything except boozing when I started my family," he noted then. "But even this last year, you know — things I wasn’t dealing with. I was boozing too much. It’s just become a problem."