It is unlikely that anything will sting the way once, when you were so much younger, your friend sat down with you to confess that his feelings had shifted and what he had thought was a bit of fun while verbally sparring was actually an attraction and he had to acknowledge it, it wasn't worth pretending he didn't feel what he felt. He'd maybe never felt this way, so absolutely physically attracted to someone he felt intellectually matched with, and emotionally too. He needed to tell you about his feelings. And you in the blush of that moment realizing that you too had feelings, that the only reason you hadn't acknowledged them to anyone including yourself was that it seemed so certain they'd be not just unrequited but ridiculous, like falling in love with the moon. But what if the moon said he loved you, what if the moon said it first? Your heart rushing to the surface of your face. "Everyone will be so surprised," you said. "Even I'm surprised!" And he said, "So... She hasn't told you?" And you realized that ahhhhhhh this another story where the only part that is about you is how well you listen; what a good listener you are. You spent the rest of the night drinking and laughing about his newfound love.
That wasn't the first and not the last time that you have realized in the middle of a story that it wasn't about you. Nobody else's story is about you; everyone is the hero of his own story. Everyone is their own main character, this makes perfect sense. And sometimes you're not a character in their story at all. No reason for it to sting, though it almost always does, the sting of salt in the eyes and you blink it away.
And now you are more than halfway through life, the sunset years, rich with purple and gold and you want for nothing, happy to be a tertiary character in every story other than your own, swelling a progress or starting a scene or two, so to speak. It's fine. But the other day when you found yourself written entirely out of a scene while someone looked you full in the face in a chapter you'd built and told you how much other people had done as though you weren't even part of it, and the salt rose in your eyes and you felt every relegation fresh, and followed it with a shot of self loathing for ever having thought, for ever having even imagined that anyone would give you top billing or any billing at all. Of course of course of course. It's never going to stop. Keep your eyes firmly on your own work. Blink it away.