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Gwyneth Paltrow says she became so depressed after the birth of her son in 2006 that she "felt like a zombie" and at first didn't understand what was happening to her. 

The Contagion star tells Lifetime's The Conversation with Amanda de Cadenet that she began experiencing the symptoms following the birth of her son Moses, even though she did not experience depression with the arrival of her daughter Apple in 2004.

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"I couldn't connect with my son the way that I had with my daughter and I couldn't understand why," she said. "I couldn't connect to anyone. I felt like a zombie. I felt very detached."

Paltrow, 39, said in the interview that she just couldn't figure out what was wrong with her and it was actually her husband -- Coldplay frontman Chris Martin -- who helped her realize what was truly going on. "My husband actually said, 'Something's wrong. I think you have postnatal depression.' I was mortified. 'No I don't!' And then I started researching what it was and the symptoms and I was like, 'Oh, yes I do.'"

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The actress says she believes "you never totally get rid" of the condition and this is why she wants to keep talking about her own experience as a way to help others. "That's why I talk about it, because even the awareness of it started to diminish it. Because I didn't feel like I'm dying or I'm crazy, period," she said.

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She added that women suffering from postpartum depression also feel a tremendous amount of guilt. "We think that it makes us bad mothers or we didn't do it right, but it's like, we're all in this together. I never understand why mothers judge other mothers? It's like, 'Can't we all just be on each other's side?'"