I don't want to sound as if I'm trivialising domestic violence against men...and indeed, the stats back up what you say - 23% of all reported cases in '09 were against men...
However, over the reported period in the official statistic, "the proportions of male victims, based on the estimated numbers of incidents, has varied between 15% and 34%, with a mean of about 24%. Since male victims tend to suffer fewer repeat incidents against them than female victims, the proportions of actual male victims are higher than those based on the numbers of incidents shown on these figures"
Basically - what that's saying is that women may raise their fists to men, but they don't do it over and over again. Once a man knows he can beat up his wife/girlfriend, the stats suggest that he will do it again and again.
http://www.dewar4rese.../DVGovtStatsAug09.pdf