A source close to Affleck tells ET that while the actor has struggled with partying and addiction issues for years, his relationship with Garner was good for him, adding that she was instrumental in helping him settle down.
The estranged couple was last photographed together in Los Angeles on Feb. 5, though sources revealed to ET earlier this month that despite reports of the couple reconciling and calling off their divorce, "there is no update or change in Ben and Jen's relationship" since they split nearly two years ago.
"Everything is moving at same pace it has been since their separation was announced," one source said at the time. "They have always remained civil and they are doing this at the pace they need to do for the best interest of their family. No specific event occurred or changed their relationship. It's the exact same status."
In Affleck's heartfelt revelation of his rehab stint on Facebook, the 44-year-old actor wrote, "I'm lucky to have the love of my family and friends, including my co-parent, Jen, who has supported me and cared for our kids as I've done the work I set out to do."
"I want to live life to the fullest and be the best father I can be," Affleck explained. "I want my kids to know there is no shame in getting help when you need it, and to be a source of strength for anyone out there who needs help but is afraid to take the first step."
"This was the first of many steps being taken towards a positive recovery," the father of three concluded his post.
Watch the video below for more on where Affleck and Garner's relationship stands.