When we get into the topic of marriage education, one huge problem is that the Church or even a school curriculum are being considered primary teachers.
Deuteronomy 6 shows us that the father (and mother by extension) are to teach all of the things in the Law to their children both day and night. The modeling of the father and mother show the kids the importance of marriage and how it should work. The Church/gatherings/assemblies are to reinforce this to show that the whole community accepts God’s standards and practices them.
The Church itself is to be a supplement. It’s not an answer. This is why families without strong and good role models (and those especially without a father) have large statistically bad influences on children even if they go to Church. There’s no primary good modeling.
The Church and ideally education should help families to have good marriages, so that they can model those to their kids. But this is limited as it requires husbands and wives to want to do that. This is a big problem in western Christianity because most husbands and wives think it is the Church’s or education system’s responsibility to educate their kids. We can all see how that works out — young people leaving the Church in droves as they go to college.
The state of the Church is only a symptom of the decay of the family. There’s a reason why the leftists/Marxists wanted to destroy the nuclear family.