Woody Allen is reportedly struggling to come to terms with the passing of his former partner, Diane Keaton.

Keaton passed away in California at the age of 79, leaving the 89-year-old filmmaker deeply affected by the news, according to People.

“He is extremely distraught, surprised, and upset,” a source shared with the publication.

“It makes him reflect on his own mortality,” the source added.

Keaton’s health deteriorated swiftly and unexpectedly in the months leading up to her death last Saturday. However, the source mentioned that Allen was unaware of her health issues.

“He was surprised,” the source added.

Allen and Keaton dated in 1969, when she starred in his Broadway show “Play It Again, Sam.” Their relationship only lasted a few short years but they later worked together on multiple films, including 1977’s “Annie Hall.” Keaton won an Oscar for Best Actress for playing the titular character in the comedy classic.

Keaton later stood by Allen in 2018 after he was repeatedly accused of child molestation by his adopted daughter, Dylan Farrow, whom he shared with ex-girlfriend Mia Farrow. Dylan’s allegations had come to light again due to the #MeToo movement.

“Woody Allen is my friend and I continue to believe him,” Keaton wrote on Twitter, now X. “It might be of interest to take a look at the 60 Minute interview from 1992 and see what you think.”

During the 15-minute interview Keaton was referring to, Allen defended himself and denied claims he molested Dylan when she was 7 years old.

Keaton also continued to be friends with Allen after the director had an affair with Mia’s adopted daughter, Soon-Yi Previn, which ended his relationship with Mia. Allen and Previn eventually got married in 1997.

“She didn’t believe that any problems [involving the allegations against Allen] overshadowed the important work that he did and the work they did together,” the source told People. “So she always stood by him. He was always grateful for that. So he always felt close.”

“I’m told they used to talk on the phone and communicate,” the source continued. “Every time she stood up for him, he would reach out to her and text.”

A rep for Allen didn’t immediately respond to Page Six’s request for comment.

Allen publicly supported Keaton as well. He made a rare appearance at the 45th Annual AFI Life Achievement Award ceremony in 2017 to honor her.

“The minute I met her, she was a great, great inspiration to me,” Allen said of his longtime collaborator before introducing her at the event. “Much of what I’ve accomplished in my life I owe, for sure, to her. Seeing life through her eyes.”

“She really is astonishing,” he added. “This is a woman who is great at everything she does.”