It's glossed over quite often but women commit domestic violence crimes just as often as men. It's just that men suffer in silence & if they do speak up no-one gives a fuck. In many places if a man calls police after a domestic violence incident committed against him the police will come and arrest the man. When it goes to court women are likely to get off scott free or receive much lesser sentences/fines. The legal system protects women and punishes men.

What are causes of domestic violence?

Mental illness (in many different forms), jealousy, greed, immaturity and lack of respect for our fellow humans. Mix drugs and alcohol in with all that and anything can happen.