During the court hearing, Heaven-Leigh referred to her father as "Tawera".
"I used to call him dad but I don't consider him as a parent any more," she said later. "It hurt me a lot because, as children, we were taught to take responsibility for our actions. I always know when I have done wrong and I have always been the first to admit it and be forthcoming. It hurt my feelings and he should practise what he preached.
"I thought he should take responsibility for his actions. I was hurt. I mean do you think it is right that he should hit someone and get away with it?"
The court heard Nikau had been with the father of Heaven-Leigh's two children before the assault, but Heaven-Leigh said the incident was not about the kids, aged 5 and 6.
"The assault has nothing to do with the children," she said. "Obviously [he was] frustrated and angry at me and making a scene in the main street. I mean he pulled over and said some harsh stuff like 'you are a loser, you are a bad parent'.
"I decided that I wasn't going to take it any more - that's why I stood up and yelled back at him. That's why he got frustrated and angry with me because I have never done that before. Usually I back down. Not this time - so he strangled me."
Heaven-Leigh said she believed her father should have "stepped up" and pleaded guilty to the charge.
"He could have paid a fine but he didn't take on his responsibility. That's what I really care about."
Nikau has been bailed until his sentencing on June 28.