The former Bond Girl married Sheen in 2002 and the couple went on to welcome two daughters together before separating three years later.
Speaking to Matt Lauer on NBC's Today, she said: "He's the father of our daughters and I still care very much for him and wish him well. He's also a survivor and if anyone can pull themselves together it's Charlie."
Richards, who has penned a memoir called The Girl Next Door, also told Lauer that the Sheen recently portrayed in the media is "not the man" she fell in love with.
"Everyone asks me why I married him, which I get into in the book. The man I fell in love with was very compassionate, humble, had a wonderful heart, and the behaviour that a lot of us saw in the last six months is not the person I fell in love with."
Richards also revealed that she shielded the couple's two daughters - Sam, 7, and 6-year-old Lola - from a lot of what was said about and by Sheen in the media, but said that she did speak to them about addiction, using a book specifically aimed at children.
However, the actress suggested to Lauer that her daughters are probably too young to fully understand at this stage.
Richards recently revealed that she had adopted a newborn baby girl called Eloise Joni, named after her late mother Joni.
She told Us Weekly after the adoption that Sheen had been "supportive" of her decision to expand her family, saying: "We talk every day. He's met her. He knows how much I love, love kids, so he was very supportive."
Yesterday, it was announced that Richards will take part in the upcoming TV Guide series Hollywood Mums Club, which will feature a group of celebrity mothers coming together over supper each week to discuss their lives.
Richards's memoir The Real Girl Next Door is available now.
> Denise Richards throws baby shower for daughter
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Watch more of Denise Richards on Today below: