Huh? He only has one kid- a son, who appears in a lot of the movie diving with him. I'm no expert on the filmmaker's life, but I've not heard that he 'turned his back' on his wife. In fact, you can read her feelings about his relationship with the octopus here:

https://stories.seachangeproject.com/my-octopus-teacher-and-...

She ends by saying that she dives almost every day with the filmmaker.