Nashville fans were shocked to learn on Thursday that the series had been canceled, and apparently, so were some of the show's stars.

A source on set of the ABC drama told ET that a few of the cast members "seemed pretty blindsided by the decision."

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Following news of Nashville's cancellation, the show's star, Hayden Panettiere revealed on Twitter that she was still struggling with postpartum depression and would be taking time to "reflect holistically" on her well-being. According to ET's source, nobody on the Nashville set blames Panettiere for the cancellation of the show.

"She probably just needed more help," the source said. "And her heart wasn't in it to focus on the show."

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One factor that may have contributed to Nashville coming to an end was the show's budget. "The cost of production to shoot even one episode was so high," the source said. "Everyone is just super bummed."

On Friday, Nashville's other leading lady, Connie Britton, reacted to the cancellation news. "To the amazing friends and family who are Nashville, to the cast and crew, and most of all to the fans, I'd just like to say it's been my honor to be a part of this world, to live in it and breathe it in and try to replicate it," the 49-year-old actress Instagrammed. "Sometimes we were more successful than others. But the place of Nashville in my heart is deep and permanent. I am grateful for the hard work and faith of so many who dedicated themselves to creating and supporting this show. I am forever changed for the better. Thanks for the music."

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Nashville might be over, but can we expect some new music from Britton herself? When ET spoke to the former Friday Night Lights star in June, she wasn't opposed to the idea. "Every once in a while I have a moment where I’m like, ‘Oh, that would be kind of fun,'" Britton admitted. "But, I don’t know! That is the part that scares me the most, so we’ll see."

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