‘Felt very out of control’ (Exclusive)

Blake Lively was surprised by the negative attention she received during the release of her hit film It ends with us.

The actress was “quite surprised by the backlash and drama” surrounding the romantic drama’s release last month, a source told PEOPLE.

“She felt very vulnerable and upset at first,” the source added. “During the promotion of the film, not a day went by that she wasn’t in the news in a negative light. She’s just not used to that kind of drama.”

The source says the situation “felt out of control for her.” Still, Lively, 37, who will next appear in A simple favor 2 with Anna Kendrick, “enjoys working and will continue to pursue projects she is passionate about.”

Lively is also a producer behind the Colleen Hoover adaptation It ends with uswhich has since become the most successful film of the actress’s career.

Reports of tension between Lively and director and male lead Justin Baldoni sparked a media frenzy after the two co-stars failed to pose for photos together on the red carpet at the premiere, nor did they attend press conferences together leading up to the release.

Additionally, some people online took issue with the film’s marketing campaign, claiming it was misleading for a project that deals with themes of domestic abuse and trauma. And short clips of Lively’s interviews, both recent and years old, went viral on social media with criticism.

Lively is candid about her passion for making the film and hopes it will shed light on important issues and empower other women.

“It ends with us is a story about the female experience. All the highest highs and the lowest lows. And we are so proud of it,” she wrote on Instagram after opening weekend. “We celebrated this film and delivered a message that is so important to the masses. Thank you all for embracing it It ends with us with the same love, pain and joy we had when we shared it with all of you.”

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Lively’s co-star Brandon Sklenar has spoken out about “negativity” directed at the women in the cast, writing on Instagram in part: “Vilifying the women who put so much of their heart and soul into making this film because they believe so strongly in its message seems counterproductive and distracts from what this film is about. In fact, it’s the opposite of the point.”

It ends with us has grossed over $300 million worldwide at the box office, although hopes for a sequel seem low. Hoover wrote a follow-up book, titled It starts with uswhich Baldoni, 40, owns the rights to adapt into a film, and he has suggested Lively direct the sequel if that happens.