|Nothing says "love" like an expensive rock from the earth.|
If your partner proposed to you and you were surprised (or vice-versa), then you two are probably not ready for marriage.
It's a bold claim, but hear me out. First and foremost, let me say that I'm brutally skeptical of the value of marriage as a social institution and I hardly view it as an immutable contract, but the chances are if you proposed or were proposed to in the traditional western way, then you probably think marriage is a big deal. Right about now, if you're the type of person I'm describing, you might be thinking "This can't possibly be true. Most marriages begin with a traditional proposal." You'd be right, but you'd also be forgetting that more than half of all marriages end in divorce (at least in the US). If you like fifty-fifty odds, then by all means go for it.
The next thing you might be thinking is "Well, I know my parents had a traditional proposal and marriage, and they've been together for my entire life and then some." That's sincerely nice for your parents and family, but anecdotal evidence doesn't amount to much. Especially considering the fact that we all know at least one person whose parents are divorced (unless you've been severely sheltered).
If you're the type of couple to take matrimony seriously, but yet have not for whatever reason discussed it openly and honestly enough that you can anticipate your partner's thoughts on the subject, then to me this implies that there probably are other important life issues that you two haven't discussed. It amazes me how many people know so little about their long-term significant others. Important issues too, like whether they want children or not, what their long-term goals in life are, what their political views are, what their financial situation is like, etc.
I don't mean to harp on this sort of couple, and I certainly am not proposing that only one type of romantic bond works (though some definitely work better than others). I'm merely suggesting that perhaps the reason you proposed or were proposed to in the exact same way as hundreds of millions of people before you is because of social norms and pressure, and not due to genuine desire. Keep in mind that I don't mean genuine emotion here, I don't deny that couples like the ones I'm describing feel genuine love; that's not the issue at hand. What I am saying is that perhaps sometimes people propose just because "it's what you're supposed do."
Consequently, couples rush into marriages that they're not ready for with partners whom they don't really know. Worse still, the people who tend to fall for this trap believe so much in marriage that they refuse to gracefully end the marriage when it's clearly failing. Instead, they pump an absurd amount of emotion, money, and time into attempting to resuscitate the failed marriage when it shouldn't have existed in the first place.
I view proposals as catch-22s. If you have to propose to get an answer from your partner about the rest of your life, then you aren't ready for the affirmative answer. If you're intimate enough with your partner to know that you two are spending the rest of your lives together, then you don't need to propose in the first place.