The singer and actress, 49, was diagnosed with the disease last week.
Bernie, a member of all-sister group The Nolans, now faces a mastectomy and chemotherapy.
'I'm going to kick this cancer's ass,' she says.
Bernie says her daughter Erin, 10, is inspiring her to fight the illness.
'The best thing about having a child is I have the extra strength because I want to see her grow up and I have to be strong for her,' she tells the News Of The World.
Bernie's sisters Anne and Linda Nolan have previously overcome breast cancer.
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