"I love my wife so it's serious, not a game to me," he said.
Offset told DeGeneres he decided to own his mistakes with Cardi: "I stepped to it as a man and said, 'I'm wrong.' I stepped to it as a man, and you don't have to take me back but I just want you to know I love you and I care."
She had told fans they were through in December 2018, about five months after they welcomed daughter Kulture and a little over a year after their 2017 onstage engagement, which actually followed their wedding.
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But his first attempt to woo her back flopped.
In December, he crashed his wife's set at the Rolling Loud music festival in Los Angeles, wheeling out elaborate flower arrangements that spelled out "TAKE ME BACK, CARDI" along with bouquets of red and white flowers. The "Bodak Yellow" rapper wasn't having it: she shook her head at Offset and had an inaudible exchange with him before sending him offstage.
Offset told DeGeneres that he was being "vulnerable" with the stunt, and that the negative reaction reaffirmed to him why men don't often attempt big romantic gestures in the first place.
"That's why men don't be trying to be vulnerable," he said. "Because when you do it, it's like, there's something wrong with it either way."
The new year seemed to bring a thaw in their relationship. Offset accompanied Cardi to the Grammys in January and the next month, she told reporters, "We working things out, baby."