"Brad is completely sober now and is in such a different place than he was when they were together," the source said.
"Brad is truly an introspective guy who has worked hard on himself. He has apologised to her for many things he felt were his issues in their relationship.
“He truly takes ownership for his mistakes and that has changed their relationship with each other today. They both have moved on," the source said.
Brad and Jen separated in 2005 after a five-year marriage, when he reportedly fell in love with Angelina Jolie, while filming Mr and Mrs Smith.
After the Fight Club star broke up with Angelina in 2016, it’s believed he became a changed man of sorts, which reportedly included making amends with Jennifer.
When Brad and Jen caught up backstage at the SAGS it seemed there was more on their minds than just congratulating each other on their wins, and fans are now poised for an announcement they're giving their love another shot.
While it may be unlikely the couple will speak out openly about their relationship at this stage, the photographer who took the infamous images has revealed what happened in the build-up to the most talked about interaction of the night.
Emma McIntyre, who works for Getty Images, has been taking photos backstage at the event for four years.
"The moments are really joyful and there are often encounters between winners in this area," she told People.