There are many things that domestic violence affects in society.
If a child sees domestic violence being done by a husband to a wife or a wife to a husband, those children or child will think this is okay to be this way because mommy or daddy just stand there and take it, so it must be okay to hit my spouse or girlfriend as the case may be.
Children learn what they see.
Another thing is how it affects our kids when they grow up. If they are not taught other ways then violence in resolving the issues at hand in life, they will also use violence to resolve issues as well in their lives.
Domestic Violence also affects many women later on. One who has been in a domestic violence relationship may only look for that kind of relationship later to again be another violent relationship, same with a man.
Domestic Violence can also affect a child, woman and man on how they feel about themselves, it is not just a beating that is domestic violence, but what is said to that person to bring down the person verbally, mentally, not just physically.
Even if after leaving the violent situation they may not feel worthy of a relationship with anyone, they may be scared to start over with another man or woman, that child may grow up feeling inadequate, because mommy or daddy stated so when they were younger, that child may grow up hating women because of what mommy said or men because of what daddy said.
Here are some links to also help with your answer as well.
http://www.associatedcontent.com/article/9022/domestic_violence_educating_society.html?cat=48
http://www.guardian.co.uk/society/2001/mar/12/6
http://www.aaets.org/article8.htm
Either way if you are in a domestic violence situation and/or no someone who is.. help them don't turn away, or get out of the situation or help them to do so as well, there are many safe houses all over the United States and no reason to stay in such a situation and go through the torment and abuse ever.
Also I state MEN as well as women because MEN are starting to be more on the end of domestic violence as well... even though they will not always report it.. still they are sometimes the victims of abuse and domestic violence as well..