Most people's lives are like TV shows (most would say movies, but I think lives are too episodic to be a movie) and most of those people are the stars of their TV show. They go around doing things that forward the story they are currently involved in, or else it helps with their character arch. I don't feel like those types of people.
I think of myself as more of a supporting character for everyone else's life. I sweep in and out of other people's lives to help advance their plot and/or arch through my comic relief or my rarely valuable advice (but I've only really given advice to one person and while she listens, she ends up ignoring what I say and does what she wants anyway, see how good I am at that). I have a my own character arch, but it really only happens when I'm in with those other people.
I've discussed this idea with my brothers, and they say that they are the main characters in their lives. They say they are the stars of their lives and that they don't play second string to anyone else, which I agree with, except for some recent developments. One tried to tell me that I wasn't just a supporting character, which I'm sure that other people would try to convince me of, but I can't believe it, it just doesn't work that way. I don't know why.
Maybe one day, I'll get my own spinoff and find some recurring characters of my own.