In less individualistic times, people were more conforming and their responses to situations were more-or-less similar. They shared common beliefs, taboos and impulses.
In those times, to commit oneself as a spouse to someone wouldn't have been much of a gamble. Yes, there are idiosyncrasies in people but as long as they are within the framework of a larger system of beliefs and values, and as long as more than two people lived in a house, it would not have been excruciating to live together.
Today, relationships are a minefield. Let me explain why.
In the absence of tradition and history, and due to the increasing influence of short-term trends and media sensations, the mind does not develop in depth. One has an encyclopedic knowledge of shallow matters, but a startling ignorance about the wider or deeper ones. Attention deficit on the outside translates to shallowness on the inside.
Tradition is unfashionable today. The speed of cultural change has become hyper-sonic. Anything more than a few years old is old-fashioned.
In these times, there is an absence of depth in anything one comes across, including people.
And in the absence of depth and of solidity in one's foundations, can relationships be long-lasting? Can they even be expected to last? What is one relating to, if not to someone's depth of character and his/her values and a pattern of behavior which is expected to continue long in the future?
Relationships between shallow entities cannot be expected to last. Gears which mesh with each other only lightly will slip. A depth of engagement requires a depth of the cogs in the wheel in the first place. If you are not deep, your relationships will revolve around shallowness.
And since relationships are no longer strictly required (given the advances in civilization and civic institutions and merging of gender roles), to form a long-lasting pair-bond with someone can only be due to a deep sharing of values and passions.
Remove the pragmatic need for relationships, remove the ability to engage deeply with each other (since there is nothing there to engage with), celebrate freedom and choices, and is it any wonder that people are complaining about a lack of deep feeling for anything or anyone?
Without there being any external needs or pressures, can you commit five decades of your life to someone who you know only superficially, who you CAN only know superficially because there is nothing there except superficiality?
Maybe love was always of the superficial, maybe beauty was always skin-deep, but when traditions were still strong, when the super-ego was still functional, you knew that statistically speaking, you were committing to someone you intimately knew. Because you understood what made that person tick, where that person derived their values from.
Not anymore. Today, the general relationship advice is to know someone for at least a couple of years before you commit to them. And why such a long time? Because it takes that long for all the idiosyncrasies and individual morality to come into full view. You cannot trust that the person is a product of a certain kind of society, except if by "certain kind of society" one means a society where there is a chaos of values and everything is just a matter of being cool.
How can there be anything more than infatuation, attraction, satiation, and eventual boredom in these times?
It is dangerous to commit to someone if when you look into his/her depths, you see nothing, or worse, if you see chaos.
Love and courtship leading to a lifelong commitment will be remembered as a twentieth century phenomenon in human history. There will never be a mythic love story, say something like Heer Ranjha, in the future.