You can probably get away with a lot of completely unromantic things if you subscribe to one idea: the idea of true exclusive love. The idea that, off all the 6 billion people in the world, there is one, just one, who's the perfect match for you. Who if you met them, you'd drop anything and everything and spend the rest of your life together and everything would be wonderful and no problems and no arguments (unless that's what you're looking for, in which case plenty of them). Basically, this one person is the solution to every problem you've got, and you're the solution to theirs, and once you get together, like Voltron, you're an unstoppable force.
You've seen them, or at least heard about them. Couples who, at 80, still love each other like they did seven million years ago when they got married, who are still frisky and make out in public and do all of those things that people in love do. And you're convinced that they've found it, the singularity: the true exclusive love.
Well, what if it doesn't exist? I don't mean that in a bad way. What if, out of a random group of 1000 people of the appropriate sex(es), there's probably a person or two with whom you wouldn't mind spending the rest of your life? Somebody with whom you've got enough in common to make a relationship work? Doesn't it seem more likely that this is the case? And wouldn't that be amazing: look at how much better that math works in your favor: one amazing incredible outstanding generally fantastic person, or thousands of people with maybe a couple fewer adjectives in front of their noun. Or maybe not. Hmm...
But, once you've got one, you can't treat that person like they're an interchangeable part, as it were. Nope, you can't do that at all. Everybody wants to think that once you've found love, you've found the one love to end it all, and everybody wants to be treated like that one love. Because we're afraid of the limbo time between people. We're afraid of being alone, being rejected, not having somebody with whom to go to the movies or go on walks with or make out with without having to ask politely or make some slick combination of socially pre-defined moves. We're afraid of what the possibility that there are thousands if not millions of people out there that you could marry and be happy with (if you wanted to) means. We don't like to be a dot in the universe. It's one of the things that makes humans great and one of the most frustrating things in the world to deal with.
I miss eating burritos. There's not a Mexican in sight in this country. South of the border they do speak Spanish (except they call it Castellano), but their idea of a tortilla involves eggs and potatoes down there. It's sad, but we make do. On fait avec...