You know, while I would never advocate for a parent to take their kids and run off to the Dominican Republic or something, this is the kind of story that makes me understand why some do.
The laws do not protect women and children sufficiently. And proving that a drunk is an unfit parent is close to impossible. You just have to protect the kids as best you can and trust that sooner or later he either hits bottom and finds recovery or screws up so bad the justice system actually notices.