As long as there is other evidence to support a conviction, a domestic violence case can move forward even without the victim's cooperation. And in the event that the alleged victim doesn't show up to a preliminary hearing, this doesn't mean that the charges will be withdrawn and the case dismissed. Furthermore, if the victim is subpoenaed as a witness, a subpoena is a judicial order to appear and if they ignore it, they can be held in contempt of court and an arrest warrant can be issued.