A source tells PEOPLE the on-off couple got back together a year ago: “It’s never been the easiest one though since they both have families”

Jennifer Garner and boyfriend John Miller are happy together after taking some time apart, a source tells PEOPLE.

“They have a very special relationship,” says the source, adding that the couple rekindled their romance a year ago. “It’s never been the easiest one though since they both have families. They took a long break from dating, but Jen is very happy that they are back together.”

The pair first connected back in 2018, shortly before Garner finalized her divorce from ex-husband Ben Affleck, with whom she shares three kids — Violet, 17, Seraphina, 14, and Samuel, 10. Miller, who is chairman and CEO of Cali Group, owner of the CaliBurger restaurant chain, has two children with his ex-wife, violinist Caroline Campbell.

By 2020, it seemed that Garner and Miller had broken up. The following year, however, the couple appeared to be back on when they were spotted spending time together on several occasions.

Garner and Miller — who are private about their relationship, having never spoken about their romance publicly — were photographed over the weekend holding hands on a walk together in Santa Barbara, Calif.

Ben Affleck Laughs While Chatting with Ex Jennifer Garner’s Boyfriend John Miller

John Miller, Jennifer Garner. BACKGRID; SHUTTERSTOCK

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When Garner and Miller started dating five years ago, a source told PEOPLE, “Although the divorce was just finalized, Jen has considered herself single for a long time. Dating is just a natural step. Jen will always care about Ben and help him be the best dad. She was very ready to move on though. She seems very excited about the future and is in a great place both personally and professionally.”

Garner, 50, told PEOPLE in March 2021 that the idea of getting married again wasn’t an immediate thought.

“I don’t know. I’m so far from it. And I don’t know that marriage would need to be a part… I mean I definitely don’t think that I’ll be single forever,” she said at the time. “But this is not the time. I don’t need to complicate it. I’m good.”