The Greeks have four words for love. There is agape, or spiritual love; storge, which is familial love; philia, which is the love between friends; and of course eros, sexual love.

I have problems with all four. Eros is a wasteland for me and always has been. My family is a source of constant trouble, much of which I cause myself. And I’ve been spiritually dead for quite a while; agape was a comfort for years but has been the worst of all in the last year.

My current problems are with philia. I value friendship highly — perhaps too highly — but I don’t think enough about its meaning. Assumptions are dangerous; the expectations for spiritual, familial, and sexual attachments are defined much better.

Friendship, though? People use the word “friend” to describe every level of intimacy from acquaintance to sexual partner. The rights and responsibilities of friends are defined by each person individually. One person may believe that “friend” means someone who would die for you, and another thinks it’s just someone with whom he’s friendly. To complicate matters, many people distinguish among their close friends, a circle of friends, and acquaintances but don’t make that explicit, and use the word “friend” to describe all of these. I’ve seen complete splits between friends over the definition of the friendship, where one believes that a friend is someone who lends money, or shows up at the wedding, or stands up for you no matter what, and the other has a more casual view of the arrangement.

All of this confusion can occur without anyone being malicious or even neurotic. The meaning of friendship is fluid, and assumptions go unchallenged for years. What’s worse, people change their idea of friendship sometimes without realizing it. Think of children and their lists of friends and enemies written down in deadly seriousness. You’re my best friend; she’s my second best friend; he’s my enemy. Thirty years later they may have only casual friends and be deep in family life.

I’m in a strange position. I’m forty and single, without much family. I have friends from college who live mostly in Los Angeles; I rarely hear from them, and I find it hard to connect with them now. Years ago they moved on to other stages of life and left me behind. Part of the bond of friendship is shared experience. When I left the entertainment industry, when they all got married and bought nice houses, when they found their own new social circle, I didn’t belong so much. On some nonverbal level the friendships got awkward and were discontinued except for a few letters a year. I learned a lesson, but not well enough.

I have some friends from jobs, too. Once again, these mostly fade after the environment is gone, in just the same way as the college friends. Once again, the people I knew there changed their lives (as I did too, probably), and the bond got weaker as we had less in common.

My current circle of friends are mostly regulars at a coffeehouse near me. They’re a lot like me in some ways: intelligent, verbal, interested in ideas and arts and entertainment, funny. Most of them are at least ten years younger than me. It’s a loose group with subgroups, and not everyone likes everyone else, but it functions as a circle of friends pretty well.

Over the years this group has changed a lot. Most of them were very young then, and are near 30 now. The ones who went to graduate school or to drink themselves to death or some other final destination have departed. Others are maturing and moving on to other lives. Quite a few have moved out of state or are planning it; several are married or engaged. I remain at the table: the aging bachelor dilettante who hangs out. Not only are my friends people I can’t experience eros with, but the philia is starting to look bad.

Apart from the personal anguish this causes me (it’s not a role I enjoy), I can see the bonds of friendship stretching in a familiar way. I have much less in common with a thirty-year-old married couple with a child and a condo than I do with a twenty-year-old sophomore with a rock band and a Marlboro habit. Whatever these people actually think of me as a person (which is another problem entirely), the common ground of friendship is shrinking. This is intensely painful for me, even though it’s at least the third time it’s happened.

So what does this mean for philia, and me? It means that friendship is far less than I want it to be, and that my own unspoken definition of the word is too strong. It’s not that anyone I know is a “bad friend”, or that I have a “bad” circle of friends. Because of my own flaws, I remain the same while they move on. Because of their own life patterns, they adapt, grow, and find new ways to relate to others that aren’t compatible with the world of the coffeehouse slacker.

In my own way I’m still on the playground in grammar school, where friendship is all you’ve got. Without agape or eros and with troublesome and painful storge , I’ve hung on to an outdated philia that doesn’t make sense to people with grown-up lives.

Not for the first time, I find myself a child in an aging man’s body, looking in wonder as the adults go about their business. How do they do it? Why can’t I? Who will be my new friends?