In a year-end Facebook post, she thanked her long-time girlfriend Amber Laign and several others for their love and support.
"I am grateful for my entire family, my long time girlfriend, Amber, and friends as we prepare to celebrate a glorious new year together," she wrote.
The message, which follows Roberts' battle with a life-threatening illness, is the first time the ABC News anchor has publicly acknowledged her 10-year, same-sex relationship with Laign, a massage therapist from the Bay Area.
Roberts' post was confirmed by ABC News spokeswoman Heather Riley.
The past few years have been tumultuous for Roberts.
In 2007 she revealed that she had breast cancer. Roberts later went into remission, but in June 2012 she revealed that she had MDS, a blood and bone marrow disease.
Her sister, Sally Ann, served as the donor for a bone marrow transplant that Roberts underwent in September 2012. She also thanked her in the post, saying, "I am grateful for my sister, Sally-Ann, for being my donor and giving me the gift of life."
Sunday was the anniversary of Roberts' 100-day milestone following the transplant.
In May, Grand Central Publishing announced Roberts, one of the most popular figures in morning TV news, will write a memoir about her battle with MDS and the life lessons she continues to gather following her return to "GMA" last February.
(The Associated Press contributed to this report)