Lately on my daily walk with Stella, our nine-year-old Cairn Terrier, I’ve thought about the many friends that we’ve walked with over the years. With twelve moves in my adult life, including four in the last seven years, I am keenly aware of the difference between an acquaintance, a colleague, a neighbor, and a friend. Friendliness and sociability with people who I see routinely is meaningful-we all need human contact-but not many of those relationships rise to a level of friendship. Beyond shared interests, friendship takes time, effort, and includes a bond of affection for one another. No matter what Facebook says, a friend is not made with the click of a mouse.

In moving every two, four, or six years, I learned not every friendship made, lasts. Nor could I take my friends with me when we moved, at least not physically. The moves taught me to consider the depth of my friendships, to differentiate between friends-for-now, lifers, and foxhole friends.

“Friends-for-now” are friends of convenience. These were handy friendships with a jumping off point of shared experience; they held camaraderie and kindness. They were the people with whom I shared the same orbit, like fellow alumni I met for happy hours, or the school parking lot moms with whom I waited at dismissal, or the library volunteers, or the fellow parents cheering on the sidelines. Sometimes we became close friends, and a couple of times they were the surprise friendship that stuck after we moved. But generally, once we moved and “the now” was gone, what remained was pleasant memories and a few years of exchanging of Christmas cards.

Then there are the lifers, a term my kids coined. This is good pal-a teammate, classmate or neighbor-whose friendship grew over the years and when we moved, the friendship held and continued to grow. The advances of technology, including free long-distance calling, email, texting, Facebook, Snapchat, Instagram and Facetime made keeping-up easier. These friendships survived and thrived regardless of the distance, moves, and years because of the effort we made to see each other. And once together, we haven’t missed a beat, whether it’s was weeks, months or years since our last visit.

And there are the foxhole friends, a term used by the husband of our first foxhole friends-I use it, sparingly. I like it better then best friend, which sounds too singular and all encompassing, as if one close friendship is best over others. A foxhole friend is a friend in the trenches of life-watching each other’s kids in an emergency, listening to the honest worries that we hesitantly speak aloud, or reveling in an accomplishment of our own or our kids because we know the hard work behind it. These friends are my first calls or texts in life’s worst and best times.

At fifty-six, while I’m pleased to have a host of lifers, these dear friends are scattered about the country and the globe. The kids are gone and the easy access to shared experiences with fellow parents are gone with them. The days of meeting people volunteering at school or cheering for teams is over. I’m on my own now looking for friends in a new city. I follow the advice I’ve given repeatedly to my kids for finding friends-for-now: get involved, try something new, be friendly. But I’m also keeping the further advice I gave the kids when hoping a friend-for-now would be a lifer: choose wisely, look for shared values, and make sure they are good people. And whether they would agree, I believe that my closest friends are smarter, nicer and kinder than me and I like that, because they challenge me, teach me, and help me be a better person.

One final note, I am not on Facebook. I need less, not more distraction. Rather, I text, email and yes, still talk on the phone with friends. And then I drive or get on a plane to be with them and always welcome them into my home.