American ideology focuses on the importance of marriage and family values and assumes that the family is at the center of almost everyone’s life. How does this compare to the way people really live?

Increasingly both marriage and the family are less central to the lives of average Americans.  

Explanation:

American has a national ideology that is called liberalism. It does not mean that we all people are in the left-wing but we are the people who believe in the set of principles. These principles were given by John Locke. John Locke believes in democracy, republicanism, and self-determinism and free expression. It is not easy to be an American who can not claim a particular ethnicity.  

Thus here in the above context, American ideology focuses on the importance of the marriage and the family values that assume the center of almost everyone's life. This can be compared by increasingly both marriage and the family are less central to the lives of the average Americans.