The "no government intervention" argument is completely bogus. The government intervenes all the time in what some would call "family matters". Things like child abuse, spousal abuse, murder (the killing of one family member by another), etc., and rightly so. Would you disallow those interventions on the same basis that you decry the intervention in the case of Terri Schindler?
Here we have a case of spousal abuse of the gravest kind. One spouse is advocating the death of another, and the evidence is conflicted, at best, as to the wishes of the individual being killed. In such cases, in the past, our culture has always erred on the side of caution, that is, actions are taken to assure that an individual is not harmed. Now, the default position is to assume that the individual being harmed would wish to be harmed. Call me old-fashioned, but somehow that doesn't seem right. Maybe it was the way my parents raised me, from the old school, who taught their children that being an insane masochist was not a healthy lifestyle.
You're pushing it. He's not murdering her.