I would venture a guess that if I asked "who are you?" that first you would give your name but is that all you are is a name? So I ask again "who are you?" at which point most folks would talk about their job and say something like "I'm an engineer" but that is not who you are, that is merely what you do for work, and so we can continue to do this for a while as people will next say things "I'm a father" and "I'm a Muslim" but with each layer we peal back we reveal that these are just superficial things and not who we are, even your body is just a vessel for your soul and so you are not defined by the color or your skin or any other physical attributes.
When we strip all of it away we are left with a great void, for many people that void represents their greatest fear, the fear of being faced with your true self. One who defines themselves by the world they can see and feel would be absolutely terrified to envision themselves separately from the world they know. The void for others represents the limitless nature of the human soul, it is vast and mysterious, and instead of being terrified by the unknown we are delighted and intrigued by it, because when you are able to separate yourself from the perception of reality the void is no longer a black pit for you fall into, instead the void is you and you are the void.
The nature of the human soul is beyond the feedback we gather from our senses, who we are is something far greater than can be put into mere words! The question "who are we" goes hand in hand with "why are we here" and for almost the entirety of human existence we have answered those questions with very limited vision.
We invented paradise in the afterlife to deal with our fear of death, we invented evangelism to give our lives purpose, and we created a benevolent God to rid ourselves of any real personal responsibility. We needed some higher purpose for it all, some way to give our lives meaning that could be quantified and recorded while we hid ourselves from the truth.
We are not separated by anything other than our own perception. We are the singularity which created our entire universe, we are not a something which began as part of that singularity and then grew into a separate entity, there was not a benevolent creator who was able to piece us together after the big bang, instead you are all of it and you are none of it at the same time, this is merely a stage for you to act out your wildest dreams in an effort to discover your true self.
You are not a mere person, you are the entire universe, your current perception does not define you. You are not just the doctor, you are the patient, the hospital, the warn sun shining through the window. You are fear, love, hate, compassion and forgiveness itself.
We live in a great drama and it is perfectly alright to allow yourself to be captivated by it and periodically lose yourself, that's the entire point in fact, but never forget who you truly are, and if anyone ever asks you "who are you" feel free to smile and say " I am".