Ben Affleck has completed 30 days in rehab, but remains in the facility, a source tells ET.
Affleck's estranged wife, Jennifer Garner, drove him to rehab on Aug. 22. The source says that after a month in treatment, the 46-year-old actor is still in rehab and continues to be focused on his sobriety.
Earlier this month, a source told ET that Affleck has "been working intensively on himself" while undergoing treatment.
"It has been an intensive challenge but he had no choice," the source said. "For Ben, this was a life-and-death situation. It was very dire and that is the main reason Jen had no choice but to get involved."
On Sept. 5, Affleck was spotted out for the first time since entering rehab. ET learned that the Oscar winner is being allowed to work out a few hours a day at his home while in treatment and is always accompanied by his sober coach and therapist.
Affleck has also been receiving visits from his rumored girlfriend, 22-year-old Playboy model Shauna Sexton, but a source recently told ET that his relationship with Sexton has those closest to him worried.
"He has been told to hold off on a relationship... but isn’t heeding that advice," the source said. "His closest friends hoped he was just dating her and would break it off after going to rehab, but he seems to get closer to her every day. The more time Ben seems to spend with Shauna, the more he seems to want to go home."
"Shauna has been a strong support for him by attending his family sessions and listening to the advice, but she doesn't seem willing to give him the space he needs to stay in rehab," the source added.
Meanwhile, ET recently spoke to Affleck's brother, Casey, who candidly talked about the actor undergoing his third stint in rehab.
"Alcoholism has a huge impact on not just the person, but also their family," he said, before referencing Garner and the former couple's three children together -- Violet, 12, Seraphina, 9, and Samuel, 6. "So, I think for his kids’ sake and for their mom, and for himself, he’s trying to do the work and get it together."
"Ben is an addict and an alcoholic," Casey, 43, continued. "Most of my grandparents are alcoholics. My father is an alcoholic, as bad as you can be, and he’s been sober for about 30 years. I’ve been sober for about six years. Ben is trying to put it together, and it can be a very hard thing to do. He has the kind of resources and time, luckily, to take the time and go to a good facility."
Here's more of ET's interview with Ben's younger brother:
Ben Affleck's Ex Lindsay Shookus Gushes Over Her 'Best Dates' to 2018 Emmys, One Year After They Went Together
How Ben Affleck's Relationship With Shauna Sexton Is Affecting Him in Rehab (Exclusive)
Inside Matt Damon's Crucial Support of Pal Ben Affleck Amid His Sobriety Struggles (Exclusive)