Why do we cry when we're happy?

It's been awhile, braniacs. But I have an excuse! A good one, I swear!

I got married to the love of my life on August 10—who I, of course, met in a neuroscience lab a few years ago.

Something inexplicable has been plaguing me the past few months, though. Getting married, including the months of stressful planning and nightmares leading up to the big day, was the happiest time of my life.

I reveled in choosing dresses and shoes, booking vendors, and constructing centerpieces. I saw my family and friends a lot over the past few months. And, after all, I was celebrating one of the purest and most joyful things that can be celebrated in this crazy, mixed-up world: love.

But, for some reason, I found myself crying a lot more. Not out of sadness or frustration or hopelessness, though.

I mean, I couldn't even keep it together while walking down the aisle—something every girl, growing up, likes to daydream about...right? (See pathetic photo.)

Most of us have heard that crying, in essence, is good for us—that it relieves us when we're sad, releases stress and toxins, yadda yadda.

So what was with my sobbing on what was inarguably the happiest day of my life?

Fainting at the sight of blood

I remember the day so well because the circumstances were so ridiculous.

It was my freshman year of high school, the Friday before homecoming weekend. Football players and cheerleaders wore their respective uniforms to class, I had a blue pawprint painted on my face, and everyone in class was antsy in anticipation of the pep rally at the end of the day.

Our health teacher put on some Red Cross first aid video to appease our restlessness. Halfway through the video, an actor began "bleeding" profusely from the arm. Just as his friend ripped off a bit of his t-shirt to staunch the blood, I saw a flash of blue jersey out of the corner of my eye.

One of the star football players in my class—a pretty massive beast of a human being—slumped down his chair then lay flat on the floor. He was passed out cold.

Do you get woozy when you see blood? It seems like an oddly dramatic physiological response for just seeing a little red liquid, right? As it turns out, fainting at the sight of blood may be a primitive reflex buried deep in our brain.

Chronic blushing: When it goes beyond embarrassment

A teacher calls on you when your hand isn't raised, and you feel the familiar sensation as your classmate's eyes immediately dart toward you. Mrs. So-and-So watches expectantly, smirking. A surge of blood races from your gut to your head and your cheeks become warm. Hot. A sheepish smile involuntarily follows. You know you're bright red, and that embarrasses you even more.

Everyone knows what it feels like to blush—whether from embarrassment, emotional stress, or even just receiving a compliment. Perhaps worse than the act itself is knowing that everyone else can see the physical manifestation of your discomfort, which inconveniently functions to further redden your face.

But for 5-7% of the population, blushing is a chronic problem—happening both more frequently and with greater magnitude than the average person. Physically, it's rather harmless—but psychologically, it can be devastating.

In late May, Brandon Thomas, a 20-year-old University of Washington student, committed suicide by jumping from his 11-story dorm. "I am tired of blushing," read his suicide note. "It is exhausting to wake up everyday and have to find little ways to avoid blushing situations."