There's a Louis CK bit about how men are the most dangerous threat to women and I believe that this is factually corroborated. Extended bit here Further, I think if you look at it in terms of social inheritance it makes a lot of sense that a boyfriend/husband is the most likely person to kill a woman. If the historical record says, in no uncertain terms, that a wife is a husband's property, then any attempt on her part to liberate herself would be "just cause" for her husband to take extreme actions. I don't think shaking off thousands of years of precedent is easy, and that entitlement is having a little renaissance in the US presently. The other side of the coin is that a lot fewer people are murdered in general, so the threat is maybe a little overblown, but the people that pose a threat are the same characters that they've always been.