"Why doesn't she leave?!"
Yeah, that's why.
Police, cafcass, family court, domestic violence charities really don't want to know. That's the truth. What they all want is for the abused woman to accept mutual responsibility and of course ALL the responsibility to coparent with a dangerous, angry nut. Any failure to coparent = blame equally apportioned. Any allegations of domestic abuse and abuse against the children = she's lying and troublemaking. Family court aren't remotely interested in abuse of the wife if not witnessed by the children. That's apparently fine. 50/50 custody is the presumption. Police arent interested until hes beaten you bloody or already killed you (they won't action rape - but they will confiscate the victim's phone, no matter how irrelevant to the actual crime).
And yet! A women who chooses to stay in a DV relationship is considered an abuser of her children and threatened by social services with losing them.
It's always the women who are blamed and seldom the women who are helped.
Women who know they are at high risk of murder (and even their children) are ignored by all, including their own friends and family - who default to assuming that she's hystercial there's a loaded word.
This is why women stay.