In a routine self-examination last fall, Harris, 40, detected a lump in her right breast. She had a clean mammogram shortly before but something still didn't feel right, so she saw a breast cancer specialist months later.
A needle biopsy and later lumpectomy led to a diagnosis that Harris did not expect: breast cancer.
"It felt like an elephant was sitting on my chest," the former Dancing with the Stars co-host says of the news.
Harris sought opinions from three different specialists and received two treatment options: A double mastectomy or a less-radical second lumpectomy with radiation.
"I was sick of feeling the way that I did in the days after the diagnosis," says Harris. "I knew I needed to take control."
And for the wife and mother of two young girls, that meant educating herself and making a decision that was right for hereand her family.
Despite grappling with the options, once Harris made the call to have the double mastectomy, "I felt so much calmer."
For more on Harris and her breast cancer battle, pick up the new issue of PEOPLE, on newsstands Friday