Your stats aren't worth much. If women were just as violent, 85% indictable crime, 88% of crimes against a person, 90% of murders and 98% of sexual offences, wouldn't be committed by men.
Secondly, in the UK a woman is killed by a partner or former partner every five days.
Third, 93% of domestic abusers in court are men.
Fourth, the stats don't demonstrate abuse which is a pattern of behaviour in order to maintain power, they are acts of violence. As I said, many perpetrators accuse their victims of abuse, the acts could be committed in self defense, they could be one off acts, the acts of violence are not defined; are we talking about a slap on the arm or strangulation?
Fifth, the stats don't include stalking, sexual abuse or homicide.
Mens Rights Activists who don't like the fact that men are overwhelmingly perpetrators of domestic abuse, like to twist stats to make out that abuse is mutual. It's not. Homicides like the one in the OP are often the culmination of a period of domestic abuse, and they happen when the abuser has lost control over their partner or former partner.
Abuse is about maintaining power and control, it's not a one of instance of violence. Women are not as violent as men, criminal statistics speak for themselves. In domestic homicide perpetrated by women, it's usually either self defense or after a long period of domestic violence.