although I persoanlly agree with you about this, we also can't blame women for actions that men do. Sure, we as women should and do know better than to trust men who are not the bio fathers, (although some bio dads and some bio moms also are not safe for kids either), it is the man in this case who killed Mariah. Mariah did not die bc her mom lived with a bf - she died bc the bf killed her. It is hard not to blame women and victim-blame bc as a society we have been brainwashed to vilify women and hold them responsible for the actions of men, whether it is rape, abuse, incest, or murder. But the fact is, the only person guilty is the one who killed Mariah. If men did not abuse, rape, and kill children, women would not need to be so careful.
Personally, knowing that men pose a risk, I will not put my child at risk. But we can't blame women for men's violence.