We're all biological machines, capable of failure. Sometimes we lose our balance and fall, sometimes we remember wrong and our mind plays us tricks, and sometimes we have internal errors. We live, and we die.
The above is nothing new, not at all. A lot of people fear death, terrified of the vast nothingness that lies beyond. If one would believe in heaven, there would be nothing horrible about death, in a way. Besides death, in that case, would be an epic adventure.
I see fear of death as a natural thing. If we wanted to experience death, the human race wouldn't exist. However, as with everything, we have to accept out mortality as a fact. We have to be oblivious to the possibility of dying by heart failure (or killed by a bus) at any given time. Fearing an impending heart failure at all times would be considered weird. Not to mention the distress it would cause the poor person.
This dillemma catches my attention. Why are we often scared about external things, when internal things could be more likely to kill us? We don't suspect a heart failure (when it happends it's called a panic attack), but some feel uncomfortable when walking outside in the dark. We hear of countless individuals who suffer disease, yet we fear external factors more. The news of a robbery or rape upset people, while cancer goes unnoticed. Somehow it's publicly accepted to be afraid of the dark and refuse to go out at night because of this. On the contrary, it's considered sick to fear internal diseases, and want to get checked out by a doctor regularly.