Also, the lifelong nuclear family is something that only really appeared after the wars. Pre-war there was no antibiotics and the rates of female death were so high that single parent families were much more common than they are today. If your worries about developments in marriage are that it will reduce the stability for the upbringing of children, I would like you to consider which eras you are choosing for comparison, as we are now living in an era that supports longer childhoods than seemingly at any other point in history.
edit - for the complaint that it is difficult to find more traditional people as spouses, may I point out that there are a number of other people who seem to be making that complaint. Presumably you could find their parental address, so that you can appear in person to make a formal request to their father to begin courting. Oh, and remember to bring some cattle.
Due to this change in society, it is difficult and becoming more so to marry in the older sense. The more people who adopt the latter meaning, the fewer will retain the older. And even those who think they do are inevitably influenced by the rest.
I don't care much more about two homosexuals claiming to have married one another than I do about someone claiming to be a prophet or the reincarnation of Galileo; what worries me is the continued removal of any meaning from marriage.