At the age of thirty, you suffer a blow to the skull. The head trauma leaves you with a rare form of partial amnesia. Though you are otherwise fine, you’re completely missing five years from your life. You have no memory of anything that happened between the ages of 23 and 28. That period of your life is completely gone; you have no recollection of anything that occurred during that five year gap.
You are told by friends and family that, when you 25, you (supposedly) became close friends with someone you met on the street. You possess numerous photos of you and this person and everyone in your life insists that this individual was your best friend for over two years. You were (allegedly) inseparable. In face, you find several old letters from e-mails from this person that vaguely indicate you may have even shared a brief romantic relationship. But something happened between you and this individual when you were 27, and the friendship abruptly ended (and - apparently - you never told anyone what caused this schism, so it remains a mystery to all). The friend moved away soon after the incident, wholly disappearing from your day to day life. But you have no memory of anyof this. Within the context of your mind, this person never even existed. There is tangible proof that you deeply loved this friend, but whenever you look at their photograph, all you see is a stranger.
Six weeks after your accident, you are informed that this person has suddenly died.
How sad do you feel?