Jennifer Lopez's forthcoming album This Is Me...Now explores her rekindled relationship with her husband Ben Affleck, taking inspiration from a series of love letters the actor wrote to her.

The letters make an appearance in the star's upcoming documentary, in which Lopez dives into the making of the album.

However, it seems that Affleck was unaware that his private love letters were going to be shared with Lopez's fan base – and the world.

Per Variety, Affleck said, "Things that are private I always felt are sacred and special because, in part, they’re private. So this was something of an adjustment for me."

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Affleck titled the love letters "The Greatest Love Story Never Told," and according to Variety, he addresses the irony of the title in the documentary.

"I did really find the beauty and the poetry and the irony in the fact that it’s the greatest love story never told. If you’re making a record about it, that seems kind of like telling it," Affleck said.

Apparently, Lopez had invited musicians to her home studio to work on the project and brought out the love letters for inspiration. When Affleck walked in, he appeared taken aback.

"Everybody thought I was crazy. And by the way, I thought I was crazy," Lopez told the outlet.

But Affleck quickly got on board with the project, as he later helped Lopez with the filmmaking aspect of her partly-animated musical film and her documentary.

"Ben told me, ‘You’re gonna write it, and then you’re going to film it. When you’re done, you’re going to do a rough cut, and you’re gonna see what it needs, and you’re gonna do three days of reshoots.’ That’s when I said, ‘I can’t do that — I don’t have any more money!’ But he was like, ‘You’re going to do a few days of reshoots, and then you’re going to go back in and edit it. And you’re going to tell your story," Lopez shared.

After seeing the final cut, Affleck said, "You made a movie. For you. You made a great movie. You did it."

"Honestly, I don’t care what happens now. That is the biggest kind of compliment that I could get," Lopez added.

This Is Me...Now will be released on Friday, Feb. 16, along with the musical film. The documentary will follow on Feb. 27.

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