Final answer:
The most dramatic change in family life over the past 50 years has been the increase in divorce rates, influenced by social changes such as divorce law liberalization and more women working.
Step-by-step explanation:
According to the provided texts, the single most dramatic change in family life in the past 50 years is higher divorce rates. The dramatic increase in divorce rates after the 1960s can be attributed to the liberalization of divorce laws and the societal changes resulting from more women entering the workforce. While various factors, including birth control information and changes in marriage ages and education levels, influenced family dynamics, the rise and subsequent stabilization of divorce rates represent a significant shift in the structure and concept of family over recent decades.