The actress, who was dropped from the series in June last year, recently signed a new two-season contract to reprise her role as Supervisory Special Agent Jenny 'JJ' Jareau.
"People were fighting for me since day one. I meant something to them," Cook told EW, when asked how she felt about the strong response to her exit. "That's not to say the network didn't think that, but it's overwhelming how fans all loved JJ and how they really felt like the heart of the show was ripped out."
Cook suggested that Jareau's popularity stems from her role as the maternal character of the show, meaning that fans were able to connect with her more easily than with other characters.
"I was never given a full explanation," Cook said, when asked why CBS made the decision to drop her. "I was never able to get full closure on it and this is why. Because it wasn't over."
Cook will once again star as a season regular on Criminal Minds this fall, and will make her return appearance on the series in the current season finale on May 18.