As someone whose case load consists primarily of family law cases for victims of domestic violence, these stories always ring home because I've seen most of these sorts of fact patterns play out and have names/faces of the parties and the kids to go along with 'em.
One thing to keep in mind, and I know that this won't sit well with the bleeding heart wing of my profession and most Domestic Violence shelters/advocates/etc., but the reason that folks who are victims of DV don't take the proper and affirmative steps necessary to address the problem and ensure their safety is that they themselves are damaged goods, damaged in ways which are complimentary to the damage that turned the abuser into an abuser. This is why they got together with the abuser in the first place; they don't see the problem the way we do, and as such don't see the solutions the way we do. Unless and until you address the underlying pathology that got the people together, you will not see a proper resolution being taken; you may, however, see the abused party turn on you after they get back with the abuser, yet again.
We had a divorce case recently where wife was violently and habitually abused over the course of many years. After months of contentious court hearings, mediation, and other stuff that made the case into a massive headache, the judge ended up talking the wife out of the divorce from the bench on the day it was set to be finalized; we can debate whether the judge pressured her into this or whether the victim-wife just waffled one final time at the last minute. Regardless, they stayed married, living separately in the same neighborhood. Husband started stalking/pestering wife again soon thereafter. Wife files a half-### petition for a protection order (on her own, not through my office) after allowing her last one to lapse (why?!); the petition gets denied. Earlier this month, husband barges into wife's residence, stabs and guts wife's new boyfriend, and runs off. He later kills himself in his car after being stopped by police. In this case a protection order wouldn't have done any good, since the guy was nuts, but the woman was nuts, too, for living with her boyfriend in the same neighborhood as her insane husband. The boyfriend is supposed to live.
Protection orders are very useful tools, especially as part of the mix in addressing custody and visitation, but they do not ensure anything in terms of safety. Sure, they may help control behavior sometimes, but this is only because the abuser wants to stop. The truly pathological abusers, the nuts, they won't stop until they're in a box, be it a concrete one with bars or one a couple meters deep in the soil.
Most victims who elect to rely on protection orders are nowhere near ready, in terms of their own psychological situation, to take the real, affirmative steps to ensure their own safety, because that will require owning up to, accepting, and making peace with the choices (and they were choices) that put them in the position they're in. And, honestly, a lot of them actually like the attention that comes from being a victim, getting services and sympathy from the Domestic Violence service agencies, and in having a ready-made excuse for every other failing in their lives.
The other wrinkle in this mix is that many victims, once they have D.V. service providers helping them out or once they have an attorney in the accompanying divorce or custody case, suddenly feel empowered and start pushing the abuser's buttons because they now feel protected by their advocate or attorney. For some this is a conscious choice, but for most, it is subconscious. The psychologists sometimes think this is a good thing - the victim becoming empowered and is pushing back - but these are the ones that worry me, as the attorney, because the victim is basically poking at a caged animal that often sees the victim and/or their attorney as a equally suitable targets for retaliation once they are no longer caged.