Sort of a complicated question, I'll try to ask. How was I born me and not another?

[Whateverist]

The fact that the mind and body aren't separate is the reason you are you and not someone else.

If you were born to someone else, you wouldn't still be the person you are right now, just born in a different situation. You would be an entirely different person - born to different genetics, exposed to different experiences.

You are you because you were born to human parents in a specific set of circumstances, to a specific set of cell divisions in the womb, to a specific set of experiences, which were equally influenced by your own prior experiences, knowledge, and intellectual capabilities/emotional coping mechanisms.

Yeah I know that the probability of being born as someone else is just the same as being born me.

But where is the contradiction in that? For example, I'm just you born as someone else. What exactly is it you think sets us apart to the point it makes any sense to ask who we were before we were born?

For that matter, if the experiment of "being born you" could somehow be run again, who is to say you'd bear any resemblance to the guy asking the coherence-bending question?