The 45-year-old actress - who has daughters Sunday, four, and Faith, 22 months, with her husband of six years - admits she has always been shy but the support of her spouse has given her the courage to try new things.
She said: ''He just gave me confidence through just being very kind to me and understanding me, opening me up to trying things, my sexuality, those sort of things.''
Prior to her marriage to Keith, Nicole was wed to Tom Cruise - with who she raises children Isabella, 19, and 17-year-old Conor - for 10 years until 2001 and she admits she relied a lot on the 'Rock of Ages' star for support because she felt so uncomfortable making public appearances.
She recalled to the November issue of Harper's Bazaar magazine: ''In those early years, it was like, 'I'm here and I'm clutching onto your arm and it all feels a little overwhelming and really strange.'
''And I was shy. Deeply shy. I didn't feel comfortable at all. But I felt very comfortable at home.''
Because of her shyness, the 'Paperboy' star says she has always been drawn to men who can ''protect'' her.
She said: ''[I've always appreciated] a bigger, stronger personality; that's what I've been drawn to. I need protection. Everyone wants to feel someone's got their back.''