It is a legitimate question that has been avoided and still not answered. Maybe it is worth 500 million to get rid of her.
It could be - of course we already have proof that he is a loud mouth bigot, a drunk and adulterer. I’d say she’d have to do a lot to equal him in the low life department.
Mel has repeated and publicly referred to his wife as a saint and stated often that she is the better person in the marriage.
Stories of Mel’s indiscretions are common fodder. See if you can find similar stories of Mrs. Gibson’s misbehavior, overspending, drunken scenes, etc.