Michelle Williams is sharing a powerful message with her new book Checking In, in which she opens up like never before about her battle with depression.

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The singer revealed to ET Canada’s Cheryl Hickey that not even her Destiny’s Child mates Kelly Rowland and Beyoncé knew about her suffering.

“I would say just some sadness, for sure,” Williams said of their reaction to news of her depression. “Now we make sure that we’re more intentional about just coming to each other, about how we are really feeling. You know, they were always a little more open with me about what’s been going on, you know, in their lives.

“I had been masking depression for so long, it took me a while to share what was really going on.”

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However, Williams couldn’t feel more blessed to have those two women in her life.

“It means the world,” she said.

“I would have never thought a girl from Rockford, Illinois, would have been in a legendary singing group and then still friends with the people she sang with. It’s unheard of.”

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Not only does the 41-year-old candidly speak about her mental health in her new book, she also dives deep into her career, which includes the revelation that she changed her first name from Tenitra to Michelle.

“Michelle is my middle name, so it’s not like we opened up a book and said, OK, this is going to be your name. Now, it was for marketing reasons, you know, in the beginning, I was like, But I’ve been Tenitra all my life, I’m going to have to get used to being called Michelle. So it stung a little bit. I’m not going to lie,” Williams admitted.

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At the time of her name change, there was another Michelle Williams in the spotlight.

“Laughing and laughter,” the singer said of how she initially dealt with mixups between the two on social media. “But then being upset because people were tagging me upset about things that she had said.”

“You don’t see in that little circle that I’m Black? But let’s get that. As I said, I’m Michelle Williams and I am Black. OK, other Michelle Williams, beautiful, amazing actress, but she is white,” she added.