Colleen Hoover is “extremely happy” about the way the film adaptation of her book “It Ends With Us” is turning out — despite backlash from fans.

“I got to see the footage they filmed thus far. I’m not a crier — I know that I write emotional books, but I’m not an emotional person — and I cried so much on set,” the author told Jenna Bush Hager on Friday at her annual Book Bonanza festival in Grapevine, Texas.

Hoover’s 2016 bestseller follows a 23-year-old florist, Lily Bloom (played by Blake Lively), who gets into an abusive relationship with a 30-year-old surgeon, Ryle Kincaid (Justin Baldoni).

When Lively was first spotted on set in Hoboken, New Jersey, in May, Hoover’s fan base, known as the CoHorts, ripped apart the “Gossip Girl” alum’s outfits online.

While shooting one scene, Lively, 35, wore patterned boxers pulled up above her belly button and a clashing pair of equally loud, patterned pants.

One TikTok user asked whether the costume was a “prank,” while another wrote, “Where in the books did it say Lily wore multiple pairs of pants?”

However, Hoover, 43, admitted she “loves” the social media roastings because they show how dedicated her readers are.

“I don’t remember describing outfits at all. I don’t care what they have on. In my head, it’s about the conversation they’re having and the story. It’s the same way in the movie,” she said.

“You’ve seen a couple of outfits that are completely out of context. I’m not worried about it.”

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Hoover — who said she has been “obsessed” with Lively since “Gossip Girl” aired in the late aughts — also stood by her decision to tap the “Age of Adaline” actress for the role after fans called her out for not casting a “legit” redhead.

The self-described “pessimist” said she “couldn’t believe” that Lively had agreed to be in the film.

“I think (Baldoni) expected (me) to just scream into the phone,” she recalled, describing when the “Jane the Virgin” star, 39, told her Lively would take on the role of Lily.

“But he doesn’t realize … I have not allowed myself to get truly excited because I’m like, ‘Something could happen. It’s not done filming. Anything could go wrong.’”

Hoover also addressed readers’ concerns that the characters’ ages had been raised in the film.

“Back when I wrote ‘It Ends With Us,’ the new adult (genre) was very popular. You were writing college-age characters. That’s what I was contracted to do,” she explained.

“I made Lily very young. I didn’t know that neurosurgeons went to school for 50 years. There’s not a 20-something neurosurgeon. As I started making this movie, I’m like, ‘We need to age them out because I messed up.’ So that’s my fault.”

While fans have been skeptical of some of Hoover’s choices so far for the upcoming film, she isn’t fazed by their concerns.

“You guys are going to be so happy. I’m extremely happy, and now my expectations are up, and I’m going to keep them there,” she shared.

Production on the project was recently halted amid the Writers Guild of America strike. A release date has not been announced yet.