The TV presenter, 54, has been fighting the disease for a year, she tells The Sunday People.
Carol, who has a column in the newspaper, opens up about finding a large lump in her left breast in February 2014 and being diagnosed with a grade three tumour two months later.
Since then - with the support of her fiancé Mark Cassidy - she has undergone a mastectomy, six rounds of chemotherapy and 15 sessions of radiotherapy.
Alongside a photo shoot displaying Carol's very short hair, she says: "I don't want to pretend any more. I kept it a secret because I didn't want anyone feeling sorry for me.
"I feel it is over now and I've got through it. I just want to be able to go out without my hat on and for people not to be bothered. I just want life to get back to normal."
The former CBB star, who used to be married to radio DJ Chris Evans, also reveals that when she told Mark - who is 21 years her junior - the news, they headed straight to the pub to get "absolutely plastered".
She adds that amidst the gruelling bouts of chemo, she and Mark have kept laughing and Mark even "walked around with Carol's wigs on".
After the interview appeared (15 February), Carol tweeted her fans with the message: "Thanks all for such lovely messages, I'm knocked out by the response to my news. But hopefully I'm ok now. Fingers crossed eh? x."
Thanks all for such lovely messages, I'm knocked out by the response to my news. But hopefully I'm ok now. Fingers crossed eh? x— Carol McGiffin (@McGiff) February 15, 2015
Carol's celebrity friends also took to social media to discuss the news.
Luisa Zissman wrote: "Just read your news. Pleased to hear your on the right side of it now & still enjoying red wine."
Meanwhile, fellow Loose Women star Kate Thornton said: "She hates words like 'brave' but our @McGiff has been really brave - a warrior - as is anyone who fights cancer."
Former TOWIE star Maria Fowler also shared her thoughts, saying: "@McGiff you are amazingly brave. My mum had grade 3 breast/c after a long battle she is now in her 8th year. Being open gives so many hope."
Carol quit panel show Loose Women in 2013, the same year she came fourth in Celebrity Big Brother.
She is planning to get married next year.
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