Do you ever think about how changed things would be if you'd made certain small decisions differently, or never saw them as decisions, or been a slightly different person faced with the same decisions, thus changing the nature or perception of your available options? You can trace backwards from current situation Y to decision or occurrence X in the past, the oldest decision or occurrence whose outcome led directly to situation Y, and it's startling how arbitrary or unconsidered decision X can seem, how nearly random, and yet that single point, that moment, was like the beginning of a series of detonations, a chain of ignitions in time that became your life and which seemed like a series of discrete events but which in actuality were connected stages of a single thing. And once these connected detonations began you had less control over them than it appeared, they started popping off one by one and you chose a certain illusion of control or directedness because that's how people live, as if the events that shape one's life constitute an apparatus with many small blinking dials.
What happened to the person you would've been if you'd made a different choice, or been a person capable of recognizing the existence of other choices? A person is shaped by his experiences. Other potential versions of you dissipate in a cloud as events occur and decisions are made. Experiences are a funnel which force you through a mold of one particular shape. Don't you sometimes sense that those other identities still somehow exist somewhere between reality and unreality?