"We always hurt the ones we love... because they allow us to hurt them rather than snap back," Gregg wrote on Instagram alongside a photo of NeNe, 51, reports people.com.
"I'm tired of hurting my wife who is only trying to take good care of me and wants only the best for me too. She deserves much more for her hard efforts and tireless hours spent on me. I pray to God to get it together... She has done no wrong... this is all on me," Gregg continued.
NeNe previously spoke on Gregg's attitude towards her in November 2018, calling her husband "mean" and "grouchy".
"I would just think if I have or had cancer, I would see life so differently! Not being mean, grouchy and evil for no real reason! But that's me. Pray for me," NeNe wrote on Twitter.
However, NeNe told her followers that the situation is more complicated than it appears.
"I'm always the bad guy so I'll take that if you only knew," she wrote.
NeNe also opened up about caring for Gregg to people.com, admitting that it's not easy.
"It's very, very hard to be a caretaker," she said.
"People call and they say, 'How's Gregg doing?' and I want to throw the phone and say, 'How the f*** am I doing? I'm going crazy over here, Gregg is wearing me out!' I am not good at this s***! I would rather hire somebody. Gregg doesn't wants me to hire somebody, but I'm just not good. I'm not good at fluffing the pillow; I'm good at buying the pillow."
"He has changed as a person, his attitude changed," NeNe said.
"I feel like that day, I lost my husband. Our whole dynamic changed. Sometimes I forget that he's sick and I need to remind myself because he's so on the edge. He's not nice, but he can't help it," she added.
NeNe revealed Gregg had been diagnosed with stage 3 colon cancer in June.
NeNe and Gregg have been married since 1997 and share two sons, Bryson and Brentt.