While Amber has been battling the disease since last year, they decided to keep it out of the spotlight until now.
Since the news has been made public, Robin and Amber have received supportive messages from fans around the country.
VIDEO: Robin Roberts shares glimpse inside Connecticut home
Most recently, the Good Morning America star shared a new photo of Amber resting in the garden at their country home in Connecticut during a recent snow day.
"My sweet Amber and I are immensely grateful for all the well wishes and prayers. May they be returned to you tenfold. Bless you all. She's in good spirits, enjoying her passion for nature and photography," Robin wrote.
"Sending love and light to Amber! Lifting you both in prayer, she's got this," one follower responded, while another wrote: "Praying for her recovering and complete healing."
Robin Roberts shared a new photo of partner Amber Laign resting at home
Robin's GMA co-star Lara Spencer also replied, simply commenting with a series of love heart emojis.
Robin announced last Thursday that Amber had told her that she was ready for the news of her cancer battle to be made public, and so as a result, she was sharing it.
The beloved TV star addressed the sad news in footage taken from inside her GMA dressing room, where she regularly posts videos at the start of her working day.
The GMA star has been with her partner Amber for 16 years
She began: "I will be away from GMA from time to time like this morning as she starts chemo." “At the end of last year, Amber was diagnosed with breast cancer,” she stated.
“She had surgery last month and this morning will begin chemotherapy.” She continued: "Thankfully, the prognosis is good and we are so thankful to our family and close friends who have known this and kept it private until Amber was ready to share it with others."
The couple with their rescue dog Lukas
The 61-year-old emotionally reflected on her own cancer battle, adding: "She and I have been together almost 17 years and have helped each other through our challenges, like my journey with cancer, it's my turn now to be there for her as she was for me."
Robin and Amber have been together for 16 years and met after being set up on a blind date.
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