"Missing the man that always had a plan!" wrote Leakes, 54. "Today is a tuff one…every year on this date we would be out celebrating you!"
"I can't believe we are wishing you a heavenly Birthday today," she continued. "I feel like you went somewhere and you'll be back."
"I miss you everyday Gregg!" Leakes concluded her post before adding, "HAPPY BIRTHDAY WE LOVE YOU SO MUCH"
The snapshot shows the TV personality sweetly holding on to Gregg's shoulder while the two flash smiles for the camera.
Last June, Leakes revealed during an Instagram Live that her husband Gregg's colon cancer — with which he had first been diagnosed in 2018 — had returned and that he was in the hospital recovering from surgery at the time.
Three months later, Gregg died "peacefully in his home" at age 66 after a nearly four-year battle with the disease, and in September, the Never Make the Same Mistakes Twice author shared with PEOPLE the final moments of his life.
"The last five days before his passing was really beautiful," she said. "All of his children were there. His best friends were there. Our closest friends were there. We all sat with him around the clock."
"We talked a lot, and we made peace with what was happening," Leakes added.
In December 2021, Leakes announced her romance with boyfriend Nyonisela Sioh when a source close to the Bravo star told PEOPLE she is "very happy right now."
Leakes previously confirmed to The Shade Room that her husband Gregg gave her this blessing before he passed: "His words to me were 'be happy, keep smiling and he who finds you, has found a good one.'"
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"I can't say [Nyonisela] hasn't helped me put a smile on my face," Leakes told the outlet.
She added that to find joy, "You have to be willing to be happy, and you have to make a lot of changes within yourself."