Michelle Williams and her daughter with the late Heath Ledger, Matilda.

Michelle Williams and her daughter with the late Heath Ledger, Matilda.

Michelle Williams says being a mother is an "incredible experience" and has completely changed her for the better.

The American actress is mum to six-year-old Matilda, her daughter with late Australian actor Heath Ledger.

"It's wonderful. I love spending as much time as I can with Matilda and watching her grow and become such a beautiful, sweet little girl," she told the UK version of OK! magazine.

"It's an incredible experience and it's totally transformed me as a woman."

Williams says Matilda has allowed her to enjoy life again. The star has learnt to be happy since the death of Ledger in January 2008.

"I think so," she admitted when asked if this is a good time in her life.

"It's taken me a while to feel really good again and to think more freely and just be myself. I have so much joy in looking after Matilda that I don't even worry that much about myself anyway. There's a lot to be said for just going about things, working on good films, making lunches and going shopping with your child."

Williams also says starring in the critically acclaimed independent drama Blue Valentine opposite Ryan Gosling helped her heal after Ledger's death.

"You could call it that," she replied, when asked if the film was a form of therapy for her.

"That film also took me to lots of dark places and sometimes when you confront sadness and fear it can resolve lots of issues in your head. What really resonated with me was how the film started with the purity and joy of their relationship and then later it's all gone and it's frightening how happiness can give way to such anguish and loss."

Williams thinks the 2010 romantic drama was a milestone in her life and career. She credits it for helping her come to terms with Ledger's death.

"I felt that I had gotten back to where I was and that I felt like myself and was rediscovering a lot of emotions that I had buried since Heath's death," she explained.

"Maybe the intensity of the film and the fact that my character was falling in love with Ryan's character had something to do with that."

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