Jennie Garner Reveals How Ben Affleck Destroyed The Family After Jennifer Lopez By now everybody already knows that Jennifer Lopez and Ben Affleck are offici…

Happy birthday Jennifer Garner!

The actress turned 46 on Tuesday, a few days after she and her family celebrated the occasion with a quiet party over the weekend.

“It was a low-key family celebration with kids,” a source told PEOPLE of Garner’s Los Angeles bash. The “backyard was decorated with a lot of balloons” and all the “guests had fun making pizza” via a pizza oven Garner rented from Olive Wood Pizza, the source added.

The guest list, which included Molly Sims and her family, was missing one notable face: Garner’s ex Ben Affleck. Although Garner and the 45-year-old actor, who filed for divorce a year ago, remain on friendly terms, the source told PEOPLE “Ben wasn’t there,” even though he was in Los Angeles at the time.

“Ben was back in LA this weekend,” the insider explained, adding that “the whole family went to church on Sunday before Jen’s party.”

The duo filed to end their 10-year marriage on April 13, 2016, nearly two years after they originally announced their split. The divorce isn’t yet finalized but is progressing, sources have said, as the two have been in mediation with leading L.A. divorce lawyer Laura Wasser to settle privately.

 Ben Affleck, Jennifer Garner a Year after Divorce Filing: ‘Things Are Pretty Good Between Them’

Since then, they have continued to happily co-parent their three children, Violet, 12, Seraphina, 9, and Samuel, 6, and spent Easter weekend together with them in Hawaii, where Affleck has been shooting his new movie Triple Frontier.

“They’re doing well, and are both committed to providing a supportive environment for their kids,” a source close to Affleck told PEOPLE. “They continue to remain cordial to one another. There is a lot of love and respect there.”

The day before the holiday, the whole family made a group trip to Sea Life Park in Oahu. “They made a family trip to interact with dolphins, sea lions and stingrays,” a source told PEOPLE. “They spent several hours at the park and looked like they had the best time. The kids were all very interested in learning about the animals. They all seem like huge dolphin fans.”

During the trip, Garner stayed at a resort while Affleck stayed at a nearby house. “Jen seemed excited about the trip. She hasn’t been to Hawaii for a while and always loved it,” added the source.

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“The kids love when they all spend time together,” said a second source.

When filming breaks on Triple Frontier allow, the actor, 45, visits the kids at home in Los Angeles. “He’s found a really good routine,” an insider said. “He’s in a great place, enjoying his work on the new film and being able to fly back to spend time with the family during downtime.”

Days before Garner and the children arrived in Hawaii, Affleck’s girlfriend, Saturday Night Live producer Lindsay Shookus, 37, also visited him.

Last Wednesday night, Garner was spotted out in N.Y.C. looking relaxed and happy. The actress, 45, was smiling ear to ear as she attended an event at the famous French bakery Ladurée.

Garner remains supportive as the Justice League star, who’s continuing his treatment for alcohol addiction, moves on. “As long as Ben keeps working on himself, Jen is happy,” another insider said. “She will continue to support him because it benefits the kids.”

Jennifer Garner and Kids Visit Ben Affleck

The actor is looking to buy a home, listed for $19.2 million, near Garner in Los Angeles.

Garner is also busy working on her fitness. Late last year, the actress shared a video to her Instagram documenting her extreme workout routine, which she dubbed the “Recipe for Turning A Mom Back into Action Lady.” Garner did not specify why she was kicking her fitness up a notch, but perhaps it’s for a starring role in the action film Peppermint, which Deadline describes as “John Wick, with a female protagonist.” The movie comes out this fall.

And as for work, Garner currently in the midst of shooting her new HBO comedy series Camping, from Girls writers and executive producers Lena Dunham and Jenni Konner. The actress has not starred in a television show since Alias, which wrapped in 2006 after five seasons.

She recently shared a behind-the-scenes photo of herself and the rest of the cast, jokingly captioning, “Let us commence. 🤗 The cast of #CampingHBO before we’re sunburned and covered in ticks.”