I recall my father decades ago saying he had no friends. My mother rushed to contradict him, saying that he had lots of friends, but my father was right, in his own terms. He did not then know people with whom he had the level of relationship with him personally which he would class as "friend".
In my terms, a friend is one at whose house I will expect a welcome pretty much any time; one who will listen with interest to my opinions and even solicit my opinions on topics of concern; who will defend my idiosyncracies to third parties as virtues, or at least some of them.
OK; I set a rather high threshold for the term. It makes "friendship" rather more rare than if you use a lower threshold. But that is only use of a term; the reality is how rare or common is a relationship of any particular closeness.
I've noted that our culture tends to emphasize our isolation from each other. Setting a high threshold on friendship participates in that tendency.
I'm wondering whether we might play the actual reality game with more success if we balanced the awareness of our separation with a stronger awareness of ways we are linked together. It seems possible that friends as I defined them are rare commodities, perhaps inevitably so by the nature of our humanity. But perhaps we devalue other ways through which we are bound together through shared work, ideas passed informally among acquaintances, or even yielding to strangers on the roadway.
The error behind some of our poor plays in the game more be less a lack of objective realism than an excessive narrowness of attention.