We want what we can't have, plain and simple.

When you're in love with someone you can't have, it's an overwhelmingly infuriating and heartbreaking experience.

Perhaps one of the most puzzling things about the human condition is how we’ve been conditioned to take things for granted. We might be gifted the most beautiful, loving human being in the world as a future spouse, but we’d immediately turn them down for someone who just is not as interested.

Because of the sheer lack of excitement that a “done deal” offers, we can find even the most attractive person boring when we compare them to the person who we just can’t have, which makes it hard to fall for people who actually would be good for us. It makes it hard for us to trust our own emotions and actually see which partners would legitimately be the best pick for us.

If you’re anything like me, you’ve probably wondered why our brains play this cruel trick on us. Well, here are a couple of reasons why this happens.

1. We are typically more upset about lost potential than a lost sure thing.

When you’re with a sure thing, you typically know what you’re getting. You can see they’re human. You can see that they have feelings for you and that they are open to this, that, and the other.

When someone’s just a “maybe,” they tend to be more closed off. This gives us space to come up with who they are in our minds or makes us think there’s more that we don’t see. This makes us wonder what the possibilities are and think that things would be better, even if the actual reality wouldn’t be that good. After all, the road that couldn’t be taken always makes us wonder “what if?”

2. Instincts are at play, too.

Instinctually, we’re supposed to look for a partner that would be the best fit for family rearing purposes. Our brains are wired to think that if a person is enthusiastic about dating us, we'd be dating down, and that we’d be losing out by sharing resources with this person.

A person who’s just ambivalent or slightly disinterested signals that they have better options, which in turn fools us into thinking that we’d be the ones dating up.

3. It’s the thrill of the chase.

Humans are natural predators, even if we’re vegans. We hunt one another, and chasing someone around is exciting. It’s sad, simple, and true.

4. It often feels like we’ve already “conquered” the sure thing.

The problem with the “sure thing” is that we are often way too confident that the person in question will always be around for us. Hint: they won’t be. But our brains won’t listen to the logic that the “sure thing” eventually will get sick of waiting around and bolt.

To our subconscious, we already see the “sure thing” as squared away, while the person who’s not actually available is still a conquerable person.

5. We think that because someone is taken, they must be desirable. 

Mother Nature makes us believe that people who are pre-selected by other potential mates have better genes than those who haven’t been selected. This is often called the "wedding ring effect," which explains the idea that women tend to prefer men who've already been chosen by another woman.

6. We always assume the grass is greener on the other side of the fence.

We always idealize people and things that we can’t have because we always just see the “Pinterest-read” side of them. We forget that person has flaws, too. And that’s why our assumptions make fools of us all.