In the Season 2 finale of Supergirl, Kara suffered a major blow. Her boyfriend Mon-El was forced off-planet after Team Supergirl released lead, one of the Daxamites’ only weaknesses, into Earth’s atmosphere to stave off an alien invasion -- and that loss has made a major impact on the Girl of Steel. At Comic-Con International in San Diego, Supergirl star Melissa Benoist revealed how Kara is dealing with that loss when Season 3 kicks off.

"It's a couple months past where we left off," she explained. "When we pick up in Season 3, Kara has very much dedicated herself to Supergirl, and I don't think she really wants to address what happened for Kara Danvers personally, because that was such a massive heartbreak for her. So the balance is a little off-kilter right now, and this season I think we're really going to explore her identity. She's really questioning whether she's a human or an alien and which she wants to be."

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"She's in National City, just really going at every possible crime she could," she continued. "CatCo's still there, but it's definitely up in the air and she's questioning her role as Kara Danvers."

Asked about her ultimate wish for Kara, she said, "I wish she could have had that perfect formula that she felt that she had with her love and her career and being a superhero and juggling all of that."

"In Season 2, she was struggling with 'Can she have it all?' In Season 3, she's really struggling with 'How does she compartmentalize being a superhero with those human feelings that are uncomfortable for her?'" added executive producer Robert Rovner. "So she ends up throwing herself more into work, which complicates all of her relationships."

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Kara has suffered a lifetime of loss, having living through the destruction of Krypton and the alleged death of her step-father Jeremiah Danvers. It seems, then, that her most recent loss has pushed her over an edge. After all, Benoist's comments here echo the Season 3 sizzle reel, in which her character says, “Kara Danvers was a mistake.” Per executive producer Jessica Queller at the show's SDCC panel, “The theme of Season 3 is, ‘What does it mean to be human?’ And all of the characters will really be exploring that character, especially Kara."

Returning to The CW on Monday, October 9th at 8 p.m. ET/PT, Supergirl stars Melissa Benoist as the Girl of Steel, David Harewood as Martian Manhunter, Mehcad Brooks as Jimmy Olsen, Chyler Leigh as Alex Danvers and Jeremy Jordan as Winn Schott, with appearances by Calista Flockhart as Cat Grant and Tyler Hoechlin as Superman.