It's my impression she was the dominate partner in their relationship. Going by what her family and friends have stated in the media and on social networking sites, I have seen lots of comments about her anger/temper and not that much about Adam. Obviously I don't know but it seems to me this could be the case.
I don't know many men that would move their seriously ill (albeit in remission) child to a foreign country when there own has some of the best free medical facilities in the world. Remember he moved to America, she didn't move to Australia, must be a reason for that.