New research by the Centre for Social Justice revealed that more than 75 per cent of teenagers aspire to be married, but Rt Rev Mark Davies said the reality of married life today is bleak.
He pointed to low rates of marriages and high rates of divorce among trends that undermine "the well-being of society and the health of the family".
In a diocesan mass in celebration of marriage in Stockport on Saturday, the bishop will say that Brexit negotiations are a "small issue" compared with the urgency of repairing marriage and family life in the UK.
He will say: "Generations to come will surely be surprised that we failed as a society, and sometimes even as Christians, to actively propose and defend marriage as it came from the hands of the Creator.
"We cannot be unaware of the disturbing trends. The number of couples entering marriage has reached historic lows; half of marriages end in divorce increasingly facilitated by the State; and according to the predictions of the Marriage Foundation, only half of today's 20-year-olds will ever enter marriage, a number which falls to less than 24 per cent among those on lower incomes."
Bishop Mark will also express concern that the Government may "further undermine" marriage as it considers proposals to reform marriage registration for the first time since 1837, including a right of heterosexuals to register relationships as civil partnerships instead of marriages.
He will say: "If the present Government is seeking the greatest shake-up of marriage registration laws for 200 years then it should surely be seeking to strengthen marriage not to further undermine it."
Bishop Mark will present his views at the Church of Our Lady and St Christopher in Romiley, near Stockport.
He will remind members of the congregation that the Church has for 20 centuries defended and proposed the "greatness of marriage" as a "path to holiness, for the perfecting of human love and as the foundation of the family".
Stay up to date with the latest news stories from a Christian perspective. Sign up to our daily newsletter and receive more stories like this straight to your inbox every morning.
