EXCLUSIVE: Yolanda Foster Says She's 'Heartbroken' Following Split From Husband David Foster

The 'Real Housewives of Beverly Hills' star says she's going through 'a difficult time' but that she's 'OK.'

It’s been a rough week for her, but Yolanda Foster said she’s "OK" in the wake of her break-up from husband David Foster.

"I keep going, one foot in front of the other,” Yolanda told ET at the premiere of the new season of Real Housewives of Beverly Hills. She and David, a GRAMMY-winning musician and producer, announced on Tuesday they were splitting after four years of marriage.

"Obviously, this is a difficult time and I'm heartbroken," she continued, "but [I'm] grateful to have my job and be dressed and up out of the bed."

WATCH: Yolanda Foster Speaks Out About Divorce From David Foster: 'Don't Judge Our Journey'

Yolanda, who has been battling a devastating case of Lyme disease since first being diagnosed in 2012, admitted on Twitter that she and her ex had been growing apart in recent years, which lead to their split.

"It's just life. I'm sure you've all witnessed a break-up. It's life. Work, my health, his job, the children -- life is overwhelming for everybody," Yolanda shared. "It's a lot of work to keep it all together."

Recently, Yolanda and her 65-year-old husband sold their 12,000-square-foot beachfront mansion in Malibu, and the two celebrated the sale with a sweet photo of themselves kissing on their breathtaking back patio in front of a stunning sunset.

WATCH: Inside Yolanda & David Foster's Shocking Split: 'Distance and Her Illness' Drove Them Apart

According to Yolanda, they sold the home so she could focus on her struggle with Lyme disease. However, her illness has come under fire from some of her RHOBH castmates this season, and Yolanda opened up about how she deals with such accusations and rumors.

"I just let it roll off my back because I have nothing to prove to anybody except to myself," the reality star explained. "To be honest with you, it doesn't faze me - I've heard it for so many years now that it goes in one ear and out the other."

According to Yolanda, she now has "laser focus" and she's directing all of her efforts and attention toward getting better so she can "teach the world a lesson about Lyme disease."

WATCH: Yolanda Foster Hints at Marriage Troubles on 'RHOBH' Premiere, Co-Star Kyle Richards Talks Split

Yolanda's daughter, model Gigi Hadid, has also been in the headlines recently for her burgeoning relationship with former One Direction member Zayn Malik. While Yolanda said she's happy her 20-year-old daughter is "loving life," she can't yet comment on Gigi's new boyfriend.

"I haven't met him yet," Yolanda said, "so I can't say anything about him."

For more on the Real Housewives of Beverly Hills star's break-up, check out the video below.