Don’t get attached to the one story that could’ve happened.
I understand how hard it is because I’ve been this person who missed great opportunities. And I was in the realm of infinite possibilities, yet my mind at that time was still attached to the “but what if that happened”.

Sit with the emotion and make peace with it by journaling or however you want to do it.
Attachment to a story that could’ve happened is just perhaps an unconscious way to miss out on everything that’s happening around you.

I saw this in my notes (2016):
التعلق مو يعني اذا شي راح أنا ماراح أعيش بدونه وأموت، التعلق فقط "الجهل في كيفية العيش بدونه"
From @essa_a_alessa ‘s open discussions (which I miss a lot)

A good translation I hope:
Attachment doesn’t mean that you CAN’T live without this thing. Attachment is simply not knowing how to live without this thing.