"My heart is broken. I lost my mom and best friend. We love you and miss you, Mom/Granny," the 57-year-old wrote. The former Today show host shared a black and white picture of her mother having a laugh at what appeared to be a party.
"She loved fiercely and was fiercely loved," Couric added via Facebook. "We miss you, Mom/Granny. Elinor H. Couric 1923-2014."
Couric opened up about taking care of her elderly widowed mother (her father John Couric died at 90 of complications from Parkinson's disease in June 2011) in an interview with Woman's Day in 2012.
"My mother's day-to-day care took on a new urgency after my father passed away last year," Couric said. "Now Mom is living alone, in the same house in Virginia where we grew up…it's full of 55 years' worth of memories, and the thought of leaving it and the life she shared with my dad is understandably overwhelming."
At the time, Couric's mom was unsure on whether she wanted to live in a nursing home. "There are no easy answers," the veteran journalist, who married financier John Molner in June, explained. "Mom sacrificed for us her whole life, and we want to help her age with dignity, as gracefully as possible."