I have this fear alot. I think I feel so insecure that I fear the death of my family members. They are my only source of connection, understanding, and help in times of trouble. I've also been focusing on the fact that I'm probably not as safe as I believe I am. I sort of had that same conception of invincibility that people often have. Bad things happen, but not to me or anyone I know. I realize that this isn't true at all. Its just an idea that helps a person get through the day without worrying to much about the future. I'm sure this isn't helping, but I'm sure any fear you have is greatly exaggerated.