I don't want to detract from the aviation side of this report but we have had exactly the same experience at our company with married personnel coming from our Australian office to the UK with their families, then things breaking up badly and the family returning to Australia, to be followed by the husband.
It seems that the higher European salaries and job opportunities that initially seem attractive are more than outweighed by expensive housing of significantly poorer standard than professionals would have in Australia, and other lifestyle issues as well. Schools, weather, overbearing traffic, crime, everything gets blamed.