Once upon a time in high school, I dreamt about a boy. Don’t let your imagination run wild yet — it was a dream about a conversation. After waking up, though, I felt differently toward him. I can’t remember if it was anger or awkwardness, but I avoided him that day at school. Whether or not he noticed my weird spell was pointless to discuss because, in reality, it had nothing to do with him and everything to do with my head. And beyond that, he was still one of my closest friends.

Unfortunately, the sudden and unilateral way that relationships shift gears is generally a more pessimistic story. Sometimes we’re the culprits: qualities we once found attractive can turn repulsive, and first-date high notes can be hijacked by hokiness. So we attempt to slyly exit scene. It’s like the book that loses its magic: the words never changed, but you find yourself wondering what you found so interesting in the first place. Other times we’re the victims: all texts, calls and communications have stopped, and we wonder how we missed the vote that kicked us off the island. Yet these lightning-speed reversals don’t come with a warning, just frustration and lingering questions: how much of our relationships are in our heads? How often do we project our own false ideas onto others, and how often do we unknowingly receive them?

I was chatting recently with a friend about this. He’s one of the most self-admittedly “nice” guys I know and truly embraces that. He tries to meet everyone halfway, on good terms, convinced that it’s possible to be friends with everyone. (Indeed, our semi-opposite philosophies about people lead to very long and colorful discussions.) He suspects that his pro-amiableness is why new relationships tend to form spontaneously before him like fire — and why, at least in his head, they end just as quickly. Essentially, his commitment to see good in the other person doesn’t always outshine the truth of personality differences and long-term issues. It’s the classic case of how we tend to see what we want to see — for as long as we possibly can. In relationships, it’s mostly a problem of timing: a promise has usually already been made before we realize it was with someone we partially conjured up for ourselves. That notorious line, “It’s not you, it’s me,” might have some real bearing here…

If only that were more comforting, though. Perhaps unsurprisingly, I have many more friends on the other side, suffering from their crushes’ seemingly inexplicable changes of heart. One of my best girlfriends, who is smart and isn’t wasting time on the subject, is simply annoyed by her slight curiosity. After all, with any new encounter, there is the chance that we inadvertently hit their relationship deal-breaker and unwittingly call the whole thing off; then comes the inevitable quest to deduce what horrific thing it was that we said or did. But the end of a thing, fling, or promise ring can also come from arbitrary personal realizations in the other person’s mind. Ironically, this could be the most comforting thing in the world: we can’t take credit for everything that happens to us (though we try very hard to, often subconsciously.)

The de facto definition of “relationship” is everything that exists and occurs between two people. In this complicated world, though, everyone brings his or her baggage on board. It’s never solely about how two people behave or feel when they’re with each other. It’s also about everything those two people are, respectively, when they are alone. Dynamics change and patterns seem inconsistent because, ultimately, we don’t all know each other enough to know what their “consistent” really is. And assuming so can lead to too many hurt feelings down the road.

But this story doesn’t end like that. Despite the infuriating nature of ambiguity, we must admit it makes the good relationship that much greater. Despite the black holes of our highly unknowable heads, we do meet people who see something true in us and — what’s more — still want to be with us. Two independent people, with their mysteries in tow, can collide at the right place at the right time…and voila! Friends, boyfriends, girlfriends — this is how it happens. And it feels like magic when it does.

This column is like a hello from Nina to you. Won’t you respond? All you have to do is email ninamc “at” stanford “dot” edu to tell her what you think. Happy Tuesday!