My running world is simple. I divide people into two groups.
Faster than me. Not.
There are some hazy persons, to be sure. Tweeners. You know the persons. Sometimes you beat them in a race or at the end of a run, and sometimes you don’t.
But you also know which camp they really belong in. Do you secretly gloat when you beat them? They’re faster. Do you worry about them all race? You’re faster, but not by much and maybe not for long.
People can move from one group to the other over time, as you get better or they get better. You see them at the track and you grumble, It's not fair! How do they have the time? So that's how they been beating me! It's time to reassign that runner.
But no one is ever not in one camp or the other for the long term. Occasional successes or failures are merely moments for euphoria or somberness. It's simple.