Jennifer Garner's Boyfriend John Miller Has Reportedly Been a 'Rock' During Ben Affleck's Relapse

Jennifer Garner's boyfriend, John Miller, has been by her side even as the actress focuses on helping ex-husband Ben Affleck during his recent relapse. Affleck appeared to be intoxicated at a Halloween party on Oct. 26, and later admitted he had a "slip." In addition to that stress, Miller's home was evacuated during the Getty fire in Los Angeles so he has been staying with Garner.

Garner "knows she can rely on" the businessman, a source told Us Weekly.

"They are very happy, and going strong," the source said of the 13 Going on 30 star and Miller's relationship. "John has been a rock for Jennifer, especially during Ben's recent relapse."

Back on Oct. 27, TMZ published video of Affleck appearing to slip and using a car to keep his balance as he left the UNICEF Masquerade Ball at the Kimpton La Peer Hotel in West Hollywood the night before. Hours after the video surfaced, paparazzi spotted Affleck outside Garner's home and asked him about the incident.

"It happens. It was a slip, but I'm not going to let it derail me," Affleck told the photographers. "Thank you very much, guys."

"You could tell that it wasn't an easy thing for him, but Ben owned his mistake," a source later told PEOPLE. "He said it happens, that he slipped up but that it won't happen again. It was a smart move because now the story is basically over... He looked tired."

Affleck only recently marked a year of sobriety, following his time in rehab last year as he and Garner finalized their divorce. He previously went to rehab in 2001 and 2017, and is still attending Alcoholics Anonymous meetings.

"Battling any addiction is a lifelong struggle. Because of that, one is never really in or our of treatment," Affleck wrote in an Instagram post in October 2018. "It is a full-time commitment. I am fighting for myself and my family."

Affleck and Garner broke up in 2015, but their divorce was not finalized until last year with she was by his side during his rehab stint. The former couple have three children, Violet, 13, Seraphina, 10, and Samuel, 7.

Miller is a businessman Garner began dating after her divorce was finalized. He is the CEO and founder of the Cali Group, a holding company "focused on using technology to transform the restaurant and retail industries," according to its website.

When the two were first spotted on a date last year, a source told Entertainment Tonight Garner's friends approved of the relationship.

"Her friends know how much pain Jen has been through in the last several years and have wanted this for her for a very long time," ET's source said at the time. "They are thrilled to see her happy. She literally has been smiling ear to ear. Right now, Jen's dating life is going so well and Ben has finally started taking his sobriety seriously, that she is over the moon -- and she deserves it."

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