I can relate to so many of these posts...
I also tended to have just one very close friend though school. Unfortunately, the first two moved away and we lost contact. During high school I had two close friends (at separate times). Of course they both had lots of other friends, but I was content just to have them. The only problem with that is, if something goes wrong in the friendship - which it did - you end up alone. I really feel I was a great friend to these two, but I always felt used and taken for granted. And of course, they both abused our friendship to the point where I decided I wasn't going to allow myself to be treated that way again.
The way I see it, friendship is a two way street, give and take. You have to put in the time and effort, and I really can't be bothered. It would be nice to have someone to ring and have a chat, go to a movie or a coffee. But then I would have to be there for them and I know it sounds selfish but I value my own time and space. Being married, working shift work and caring for an elderly relative takes up the majority of my time and what left I need for me.
Still, I would really like to meet others IRL who understand SA...