This is an important question. According to Connecticut General Statute 46b-38a, 2011, domestic violence is any incident that causes physical harm or anything that threatens physcial harm. Interestingly verbal abuse is excluded, unless it is accompanied by a threat of physical harm.
Another important point is the difference between restraining orders and protective orders. A restraining order can be issued even if there is no arrest. The threat is enough. It is a civil action. When there is violence and a crime, it turns into a crimial case. When this happens what is ordered is a protective order.
Another important law pertains to employers. They must allow time (paid or unpaid) to the person who has been abused to get medical attention and relocate, if necessary.