Constance Zimmer is opening up about something she had been carrying quietly for months. The fifty-five-year-old actress went public on Instagram this Sunday with news of her breast cancer diagnosis. Zimmer is a mother to one daughter, Colette Zoe Lamoureux, born January 5th, 2008, at Huntington Memorial Hospital in Pasadena, California. As per a report shared by People, Colette weighed eight pounds, ten ounces at birth. Colette is Constance Zimmer's only child with husband and director Russ Lamoureux. The Washington native opened up about her personal life and shared that"October is #breastcancerawarenessmonth and I never thought I'd be honoring it with my own story. On March 13th when I was away from home, I heard these words from my doctor over zoom: 'You have DCIS, also referred to as Stage 0 breast cancer.' The silence was deafening.""Here I was surrounded by women sharing their secrets about their Midlife truths and I was holding onto the biggest secret I'd ever held. First, I had to call my husband and get home to tell our daughter in person," she continued. View this post on Instagram Instagram PostConstance Zimmer learned she was pregnant days before a scheduled surgery:As per a report shared by People back in November 2007, Zimmer had hinted that her pregnancy came as quite a surprise. The Entourage actress opened up about the moment she found out she was going to be a mother. Doctors had previously told her that conceiving was simply not an option."I had been diagnosed with a fibroid in my uterus, and both doctors told me I couldn't get pregnant. Because of my age, they said 'You need to have this surgery right away.' So anyways, I had all these appointments and met with specialists and they said you definitely need to get it operated on," she shared.Constance Zimmer had been scheduled for surgery on a Friday. However, when she went in for her pre-op blood work that Monday, everything changed."The doctor came in and said 'Actually, I don't think you can have your operation on Friday' and I said 'Why not?' and she said 'Because you're pregnant.' I was like 'I'm sorry, what? You might want to go look at my file because the reason I'm here is because I couldn't get pregnant, so I don't know if that's right,'" she continued.The doctor stepped out, leaving Constance Zimmer alone in the room for fifteen minutes."She came back and said 'Wow, I don't know what to tell you, your doctors are completely amazed. Congratulations! This is great news!' And I just said 'Yeah, it is. It's awesome' … I just needed to re-adjust everything," Zimmer concluded.Constance Zimmer credits marriage and motherhood for giving her the confidence to play Quinn King in UnREAL:Constance Zimmer gained a lot of popularity over the years for playing Quinn King in UnREAL. As per a report shared by Paste Magazine, the show is a skewering satire of the reality TV dating genre, with Quinn serving as the sardonic executive producer of Everlasting, a woman who will do anything to ensure she has a hit show. It is widely regarded as the role of Zimmer's long and fruitful career.Back in June 2016, Zimmer opened up about the role in an interview with The New York Times, sharing that she could not have played someone like Quinn earlier in her career. She credited her husband, Russ Lamoureux, along with marriage and motherhood, for giving her the security, perspective and confidence to dive into the darkness of the character without being afraid she wouldn't be able to come back out of it."She's a woman who is flawed and has struggles and is insecure but is at the same time confident and independent, and it's incredible that this is what I get to play at this time in my life." she said."There's so much more about her that we have yet to learn," she added.Constance Zimmer kept her breast cancer battle private while on a very public press tour for Love Story:Zimmer portrayed Carolyn Bessette-Kennedy's mother, Ann Marie Messina, in FX's Love Story, the series centered on John F. Kennedy Jr. and Carolyn Bessette-Kennedy. She was promoting the show publicly while quietly managing her diagnosis and treatment behind the scenes."I then followed my surgeries with radiation, while celebrating my Emmy Nomination. So, me and @welcometoheidi decided to have my breast surgeon on our podcast @talkfiftytome because I know talking about it can remind women to please not wait until you have symptoms to get yourself checked in all ways possible. You can listen on 10/6 to the whole story," she wrote."I'm grateful to be CANCER FREE and thankful to @cathrinewhite for capturing me for the first time since my diagnosis, celebrating what my body got me through over the last 7 months: pure shock and fear alongside pure joy and gratitude. From hospital gowns to Emmy glamour this was one hell of a ride," she added.