I do wish there were a few more words for friend. Something in between friend and acquaintance.

I think I tend to use the word "friend" more than I should. For example, there are always people at work whose company I enjoy, but I don't share every detail of my life with them. That is reserved for a much smaller circle of people.

People can move among these categories. There are many people who were close friends at one time, but time and geographic distance have lessened that bond.

I had a similar feeling about English use of "friend" as a non-native speaker. Polish-English dictionaries will tell you that "friend" is in Polish "przyjaciel", and "znajomy" is "acquaintance". But in fact the word "przyjaciel" is used in Polish much more discriminately, for the relationships like Achilles and Patrocles (albeit without homosexual undertones) or Thelma and Louise. Eva Hoffman in her "Lost in Translation" put it much more better than I ever could (and she refers to the era long before the advent of the Internet "friends"):

We like each other quite well, though I'm not sure that what is between us is "friendship" – a word which in Polish has connotations of strong loyalty and attachment bordering on love. At first, I try to preserve the distinction between "friends" and "acquaintances" scrupulously, because it feels like a small lie to say "friend" when you don't really mean it, but after a while, I give it up. "Friend", in English, is such a good-natured, easygoing sort of term, covering all kinds of territory, and "acquaintance" is something an uptight, snobbish kind of person might say. My parents, however, never divest themselves of the habit, and with an admirable resistance to linguistic looseness, continue to call most people they know "my acquaintance" – or, as they put it early on, "mine acquaintance". As the word is used here, Penny is certainly a friend…