Ben Affleck's 'Mood Swings' with 'Big Highs and Big Lows' Contributed to Divorce from Jennifer Lopez (Exclusive)

Ben Affleck’s unpredictable moods played a central role in his and Jennifer Lopez’s divorce.

Despite their feelings toward each other, the 52-year-old actor’s extreme and sudden changes in mood ultimately drove a wedge between them, a source tells PEOPLE.

"The truth is there was a great deal of love but also unfortunately what became clear were Ben's erratic mood swings that he couldn't hide from the press, as much as he tried to,” the source says.

"You could see the erratic behavior, the giant mood swings,” the source continues, describing how the actor would go from “being incredibly happy and warm — the best light that emanated from him” to exhibiting “the deepest, darkest behavior.”

“I think he was signaling a message to the press,” the source adds. “But yet participating.”

Since April — Lopez, 55, listed the couple's separation date as April 26 in her Aug. 20 divorce filing — the duo tried to make their marriage work, but Affleck’s fluctuating mood made things difficult, the source says.

“They were trying to work through it, but when the mood swings and the big highs and big lows informed a toxicity that was pervasive, no one can help you — you have to help yourself,” the source explains.

“But I would not be so bold to say there isn't love — of course there is,” the source adds. “The world was rooting for them, but who he said he was and who he turned out to be were two different people.”

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer​​, from celebrity news to compelling human interest stories. 

Lopez filed for divorce on the second anniversary of her and Affleck’s Southern wedding in Georgia in 2022 — they legally married in Las Vegas on July 17, 2022 — after spending much of the summer apart and on opposite coasts.

PEOPLE has reported for months that the couple — who broke up for the first time in 2004 before rekindling their romance — was experiencing relationship turmoil. 

Explaining her choice to file on what would have been the pair’s second anniversary, a source told PEOPLE the singer “was done waiting and the date she did it speaks a ton.”

A different Lopez insider echoed this sentiment, stating that the star” tried really hard to make things work and is heartbroken.”

Meanwhile, the couple’s children — Lopez is mom to 16-year-old twins Max and Emme with ex Marc Anthony, and Affleck shares Violet, 18, Seraphina, 15, and Samuel, 12, with ex Jennifer Garner — come first, the insider emphasized.

“The kids are a top priority, as they always have been,” the source said.