We studied feminism briefly in a Communications course I took at the University, the prof (female) was very sympathetic of the feminist movement. I didn't make up the notion of the patriarchal society.I didn't claim you made it up; but your presentation doesn't strike me as very accurate. In particular, "It's obvious that marriage is a byproduct of this patriarchal structure" seems wrongheaded. Marriage is a social institution; that means that the structure of marriage reflects the existing power structures in society.
Even in the most egalitarian societies, like Sweden, people still get married in great numbers. What's more, many of those who don't get married in fact do get married in all but name: they live together like a married couple indefinitely. Since there are often few benefits to explicit marriage, their choice represents little more than a willingness to forgo a religious ceremony. But it shouldn't surprise us that people in very secular countries decide to avoid big religious ceremonies; that's just common sense.
When a man and a woman fall in love, the first thing they try to do in a traditional/conservative society is to try and get married. In the west, the first thing they do is go out together, make out, have sex, maybe move in and live together for years and have children without ever officially getting married.
As I understand it, a great number of unmarried couples in traditional societies make out and have sex; the big difference is that they sneak around when doing so. But if you like, we can pretend that everyone in traditional societies actually strictly observes all their social norms.
Moreover, a great many people in western countries get married and stay married for many years. It seems silly to pretend that they don't exist. Your claims would be more persuasive if they were backed up by numbers.