But what does that even mean anymore?

You would expect a neighborhood to be a friendly place.

Isn’t that how we select our homes, to some extent, because eventually we hope to feel some type of kinship with the people who already live there? We may not know them yet, but the architecture and the lawns and the cars and the landscaping tell the story of future neighbors, people we hope will become our friends over time.

It doesn’t always work out that way, though. Friendship is elusive, and mere proximity isn’t necessarily enough to make what starts as a random connection turn into something more meaningful.

Someone said something interesting to me the other day: “I really don’t like my friends.”

It started me thinking about friends and friendship: Is it possible to have a friend you don’t like? Isn’t “liking” someone kind of elemental to calling them a friend?

Something else got me thinking about friendship, too: A recent study published by the Public Library of Science concluded that only about half of the people most of us call friends would say the same thing about us.

That’s right. If you identify 20 people as friends, only about 10 of them will tell someone else they’re friends with you. And if we knew which half didn’t really like us that much, we probably wouldn’t like them much, either — not exactly a great way to build a stable of friends.

Who is defined as a “friend” and what is defined as “friendship” are admittedly vague concepts, and those concepts change with times and technology. Some of us have hundreds of Facebook friends and LinkedIn connections, but how many of those people can we count on to bail us out of a problem at 3 a.m.?

It all comes down to what we expect out of friendship. Are we satisfied calling people “friends” who know our names but not much else about us? Or do we believe a friend is someone who knows us inside-out, and vice versa?

It’s pretty easy these days, when checking out other peoples’ online accounts, to read the glowing snippets and watch fun-looking photos and videos and see the myriad approving responses from “friends” to convince ourselves that friendship is something everyone else has in abundance even as we struggle to find it.

It would be easier if neighbors or even co-workers were automatically friends, but it doesn’t work that way, either. We all have our lives to live, and for the most part, our priority is not usually someone else.

Perhaps the ultimate lesson in friendship is one I heard recently during an interview with NPR radio host Diane Rehm. She was talking about her late husband, and as a wife and presumably a friend, she seemed to have his need for friendship figured out: “He would rather have had lunch with The New Yorker magazine than any human being. Including me.”

Apparently, her husband identified the one friend he knew he could count on, and he married the one friend who helped him live his life as he wanted.