Harry Connick Jr. And Wife Jill Goodacre Reveal Her 5-Year Secret Battle With Cancer

Harry Connick Jr. and his wife Jill Goodacre are finally opening up about something they've been keeping private for the past five years — Goodacre's secret battle with breast cancer.

Connick Jr. said his life was turned upside down when Goodacre's diagnosis emerged from a routine mammogram that came back clear in October of 2012.

"They said, 'OK, looks good. Since you have dense breasts, just go across the hall for your sonogram," Goodacre told PEOPLE. But something was detected during the sonogram, and after a biopsy, Goodacre received the news that she had Stage 1 invasive ductal carcinoma. Doctors said she would immediately undergo a lumpectomy and radiation.

"I was scared I was going to lose her, absolutely," said Connick Jr., 50, whose mother died of ovarian cancer when he was 13. "I wasn't going to let her see that, but I was. I know from losing my mom that the worst can happen. She's my best friend, and I really don't know what I would do without her."

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Goodacre said one of the hardest parts of her cancer battle was telling her and Connick Jr.'s daughters: Georgia, 21, Sara Kate, 20, and Charlotte, 15. "It broke my heart," Goodacre said.

Although Goodacre didn't have to undergo chemotherapy, she says it still exhausted her.

"The lumpectomy didn't come back with clean margins," Goodacre said. "So I had to go in for a second surgery the very next day. And then radiation absolutely wiped me out. And since then there's been the Tamoxifen, which I've now been taking for five years."

Tamoxifen is an estrogen modulator taken in pill form that helps prevent the development of hormone receptor-positive breast cancers, and one of the toughest parts about Goodacre's recovery is the fact that the drug comes with some tough side effects — like weight gain.

"I've always been a pretty fit person, and so to be just rounder and heavier and not to really be able to do much about it — that's been hard. It's taken a lot out of my self-confidence," the former Victoria's Secret model said.

"It's a part of how the cancer and treatment impacted her, and it was a real issue, even though she will always be the most beautiful woman in the world," Connick Jr. added.

Goodacre is looking forward to stopping Tamoxifen soon at the five-year mark and preparing to tell the world about her battle, which few outside her family knew about for the past five years.

"It wasn't like we were superstitious, like if we said something about being in the clear we'd somehow jinx it," she said. "But we wanted to be well on the other side of things before we told everybody. The doctors all say that after the five-year mark, things look optimistic, so we're starting to feel pretty good."

"It's not something that's just going to go away like it never happened," she added. "I'll always be a little nervous, always having to get checked, always hoping it doesn't come back."

On Thursday's episode of Connick Jr.'s talk show, Harry, the couple will candidly discuss her journey and the day she was diagnosed in a heart-to-heart discussion.

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"All I wanted to do was grow old with you and have as many years as possible as I could with you," Connick Jr. told Goodacre in a PEOPLE sneak peek of the interview.

Goodacre told him, "You always used to say that: 'I just want to grow old with you.'"

"It's true," he answered. "I wanted to know what you would look like older. … I made the right decision."

Photo Credit: Instagram / @harryconnickjr