Mark J. Penn points out in his book, Microtrends, that there are 109 million straight adult women in America for 98 million straight adult men for a straight sex ratio of 53-47. However, this ratio is even worse in the black community where it starts out at 56 - 44 due to the high rates of death of black teenage boys, but due to the high incarceration rates of black men it moves the ratio to even greater disparity at 57 - 43. It appears that the fact that so many black women are single mothers has as much to due with societal structural issues as it does with any moral failure to support the traditional family structure. The simple fact is that there are not enough males around who are available to black women to marry and to participate in family life.
As long as black men keep getting killed and incarcerated, the black family will tend to be headed by females. And black men probably turn to crime because of low employment and consequent poverty. Lacking good male paternal role models the vicious cycle gets perpetruated. Perhaps if there were more good jobs for black young adults, they would marry, settle down, and stay out of crime and prison, and be there for their wives and children.