Why Angelina Jolie and Brad Pitt’s Divorce Has ‘Dragged on’ for 8 Years: ‘Neither Will Let It Go’ (Exclusive Source)

As Angelina Jolie and Brad Pitt get closer to settling their almost decade-long divorce dispute, the saga has taken its toll on the former couple.

A source tells PEOPLE that prior to Jolie filing for divorce from Pitt in 2016, "their disagreements took over" in the relationship, adding that things "turned nasty and it was not a good situation for anyone."

"All the bitterness is partly why the divorce has dragged on for so many years. Neither will let it go," says the source.

The former couple share six kids (the youngest, twins Vivienne and Knox, turned 16 earlier in July), and they were declared legally single by a judge in 2019.

Says the source, "You’d think they would be over it and just settle."

A separate insider tells PEOPLE, "Both of them were having issues with each other. The differences added up over time. It's really sad for the children, but also the parents. Divorce, especially one so high-profile, can be challenging for the whole family."

"They both care," the insider adds of their long divorce process. "They both care about the children."

Angelina Jolie Source Claims Brad Pitt Is Using Latest in Winery Legal Battle to 'Punish Her for Leaving'

Another source recently told PEOPLE that Pitt, 60, has "virtually no contact" with their adult children, however, per his agreement with Jolie, 49, "he has visitation with the younger kids." About their back-and-forth on the divorce negotiations, the source said, "Both sides are still talking, but it's not done yet."

Lately, Pitt has been filming F1 in the U.K., where he was spotted spending time with girlfriend Ines de Ramon. Jolie, meanwhile recently won a Tony for producing Broadway's The Outsiders, and she's keeping "focused on her kids and work," as one source said.

Separate from their divorce proceedings, Pitt and Jolie continue to be at odds in a lawsuit over her sale of her portion of their French winery, Château Miraval.

Pitt sued Jolie for selling her shares in the company, claiming she did so without his approval and defied an agreement they allegedly had. Jolie has responded that she didn't want to sign the NDA that came with Pitt's deal because she didn't want to be silenced from ever talking about Pitt or his past behavior. Pitt's legal team has argued that the NDA was a standard business move.

Angelina Jolie Asks That Brad Pitt 'End the Fighting' by Dropping His Winery Lawsuit Against Her

Jolie's lawyer Paul Murphy, in a previous statement about the winery battle, said, "Angelina looks forward to the eventual end of this litigation with its false narratives that continue to hurt the family and interfere with their ability to heal."

Pitt's lawyers have accused Jolie in court filings of taking "efforts to turn this business dispute into a re-litigation of the former couple’s divorce case."