Do you think this is because you fear others seeing "you"?

Trauma takes away from one's sense of safety and self confidence and ability to "trust" overall.

From what you have shared of yourself, you have been one to protect others from "seeing the bad", you did this all your life. This was something you deeply imprinted when you were not allowed to see something "bad" which was when you were not allowed to see what happened to your grandfather. You also saw how much that tragedy affected those who did see it. When that happened "you" were protected so you knew that was important, and important that you were shielded from "seeing the horror".

When your father did something tragic, no one protected you from seeing it. I think your mind is having a very hard time with this. This is not supposed to happen, especially for you in that you were so devoted to protecting others from seeing, to the point where you were exposed to some very horrific things. You were able to disconnect in that it was not personal to "you" and your effort was a form of protect/prevent/shield. This trauma is different, this is personal. Also, in that the equation of prevention is very different. This experience doesn't fit into how you navigated trauma before, no matter how bad it was, it was not "personal".

A doctor can work on many patients, deal with losses even, yet the entire equation becomes very different if that doctor fails to save/protect someone in his family where it becomes more personal. This is also similar to when soldiers form strong bonds with other soldiers and a soldier fails to protect another soldier that he deeply bonded with who is lost in the battle, it becomes so personal it dramatically changes the entire experience to becoming very personal loss.

You have been deeply traumatized when it comes to a "personal bond", so it would make sense that you shy away from personal bonds which begins through direct eye contact.