I have a friend from high school. It’s the classic sentence that starts every character evaluation, diagnosis, and competition. Maybe it’s because high school is frozen in a space outside normal time where friends became more than the person who sat next to you in social studies. Close friendships have an undeniable power that can affect people long after childhood. Especially for women.

A UCLA study reports that female friendships are unique in the sense that they help biologically reduce stress. A ten year Australian study found that friendships can improve brain functioning as we age. Study after study shows that friendship is not only good for our social lives, but also for our physical and mental well-being. The relationships we build with those around us help shape our entire lives.

I met my oldest friend in a hallway while avoiding the cafeteria. She was playing a guitar and sitting on the windowsill. Although I had no idea who she was at the time, I was instantly drawn to her in the way that teenage girls are drawn to the covers of Cosmopolitan magazine. She was the kind of person that could sing without being self conscious in a busy upstairs hallway of a public high school. Unlike me, she was not trying to be invisible. She was vibrant.

The characteristics that are intrinsically hers, are the ones I like best. Perhaps because they aren’t mine and don’t run in my family, I am more fascinated by her ability to survive off an entirely unique set of skills. She is flexible. If plans change, that’s fine. If I absolutely have to listen to disco in her car, she doesn’t think twice. She isn’t afraid to wear the kinds of clothes I privately watch on eBay year after year without buying. She can dye her hair even when there’s no real occasion.

This isn’t to say friends don’t have similarities. While people gravitate toward what is different, they ultimately crave comfort. My friend and I both analyze ourselves, each other, and everyone else for hours without getting bored. We both like walking with no particular direction. We both share the same tragically-beautiful taste for Joy Division. Yet, like most friendships, there are parts of her that have somehow melted into my personality.

Standing in a grocery store, I panicked when the pierogi section had been replaced with frozen yogurt and snack food. I could feel myself getting antsy. This is not a big deal, I told myself, scanning the sections of neon-colored dessert. My rigidity has caused one anonymous friend to sign me up for the AARP. I now have daily reminders in the form of hearing device catalogues and coupons for reading glasses. It’s not that I’m afraid of change, I tell my friends. I just like things the way they are.

I thought about slamming the frozen freezer door and waltzing out of the supermarket in a huff, when I remembered my friend and I, standing in a 4-hour line at an airport. She explained to me the problem with J.Crew and together we made up stories about the other travelers. When they told us we’d have to board another plane several hours later, she pulled out a book. We’d just have to take another route, she explained when I continued to ask what happened.

After intense scrutiny of all artificial flavors frozen, I figured the other packaged food couldn’t be horrible. I settled on a foreign container of spinach appetizers and continued on. I could safely say I was not afraid of change. An inconvenience, yes, but not terrifying.

It’s a microscopic example of contagious virtues, but there are dozens of them. They may seem too simple to pay attention to or too small to notice, but as with every deconstruction of patterns, flexibility and open-mindedness becomes second nature.

Friendships broaden horizons in a way that family cannot. While generations of families pass down ethics, morals, character, and biology to their offspring, friends pass down the shine of something new and different. Like democrats or republicans who rely on Facebook for news, people can often find themselves trapped in an echo chamber of insular thinking. While it may be rewarding to find a sense of predictability, the ability to learn new ways of thinking becomes more difficult.

Repetitive thinking, depression, and poor physical or mental health can plague someone at any point in life. While not everyone is able to still have the friend that glitters from high school, relationships outside family are important at any age.