Society specifies that certain relationships possess certain implicit privileges and responsibilities.

When lovers enter a romantic relationship, they form a social contract: conventionally, both partners—implicitly or explicitly—agree to only see each other, to grant each other physical privileges, and to observe certain rituals and traditions.

As such, expectations are built and codified into our social behaviors: we frown upon infidelity, sexual promiscuity, and push intimate friends (usually of the opposite sex) to get together with the assertion that they are “totally cute together.” Society defines clear boundaries between the behavior expected between lovers and the behavior expected between friends.

The reason these boundaries exist is so that, ideally, heterosexual couples can form stable, committed relationships so as to birth and rear children as efficiently as possible; all of our social conventions and morals are rooted in what was once, in the development of the human race, Darwinistic need: back then, humans were substantially threatened by disease and wild animals and nature, so the only way to ensure the biological preservation of our species was by having many children with the assumption that only a fraction of them would survive into adulthood. Sexually promiscuous individuals would lead to the birthing of too many children who would not be taken care of properly, infidelity would break stable familial units and so jeopardize the rearing of children, etc—so we developed a system of morals to punish behavior that threatened the continuation of the human race.

In a society of such clearly defined boundaries (one in which the need to maximize survival does not exist any more, I should add), what happens to those who fall in the gray?

What’s complicated about love is that the human phenomenon of love is composed of three separate brain systems: lust, romantic love, and attachment. You can lust after one person while romantically attracted to someone else while attached to a third person. Not overly complicated, right? You can lust after and be romantically attached to your lover (or even two different people, which is not accepted in monogamous societies), and be attached to your friends, right?

It’s not even that simple. The chemicals which are associated with each of the three brain systems usually aren’t associated to one brain system exclusively. For example, oxytocin, the neurotransmitter responsible for trust, for emotional bonding, released when you shake your boss’ hand or hug your friend, is also released upon orgasm—hence, friends who attempt to have no-strings-attached sex can end up falling in love with and becoming emotionally attached to each other.

So, even though we have complex neurologies and thus complex needs, society expects us to fit our desires within a narrow subset of categories: love for a friend, love for a lover, love for family. And so those who fall between the cracks, who occupy a gray area, are often punished by a mixture of ostracism, social disapproval, and internal confliction. How many close friends, straight or gay, have struggled with the realization that their affection(s) may not be entirely platonic? How many have mentally punished themselves for being sexually attracted to a friend? And let’s not even talk about incest.

Here’s another important fact about the human brain: the rational left half of our brain is connected to the emotional right half by only a thin collection of fibers called the corpus callosum. Neither half has any control over the other; in fact, the centers of our brain responsible for emotion and desire are completely irrational, incapable of even processing language.

Lust and attraction cannot be rationalized away. Ultimately, instead of forcing our feelings into little boxes and tormenting ourselves when they don’t, we should realize that our needs and desires are complex and not at all shameful. If we could only create healthy, mutually respectful channels for us to express and fulfill our desires instead of suppressing them and creating cultures of shame around taboo, we would be much happier.

As my mentor said, “you have the right to ask for anything from anyone. And they have the right to say no”—regardless of what society expects.