Williams told CBS‘s The Talk programme she had told manager, Mathew Knowles (Beyonce’s father), how she had felt.
She said his response was, “You all just signed a multi-millionaire dollar deal, you’re about to go on tour, what have you got to be depressed about?”
Williams said, “I got really, really bad… to the point I was suicidal.”
Williams, who is now 37, said she “got to that place that’s so dark and heavy” when she had been about 25.
“I didn’t know until I was in my 30s what was going on, I just thought it was growing pains, I just thought I’m turning into a woman.
“I’ve been suffering since the ages of 13 and 15.”
Speaking about Mr Knowles, who steered Destiny’s Child to become one of the world’s biggest bands in the late 1990s and 2000s, Williams said, “Bless his heart… I think he wanted me to be grateful, which I was, but I was still sad.”
Destiny’s Child recorded hits including ‘Say My Name’, ‘Bootylicious‘ and ‘Survivor’ before splitting up in 2006.
Williams has enjoyed a successful theatre career in recent years, starring in both Aida and Chicago on Broadway.
She has also toured the US in The Color Purple and Fela! And she took part in Strictly Come Dancing in 2010.