Some of the reasons for being afraid to die as listed online are:
• Fear of the Unknown. If one thought there was the possibility of something unpleasant you would think they would seek a path that gave them the thought, even if mentally, that there is something past death they can count on.
• Fear of Pain and Suffering. That is a self-delusion in my opinion. One can suffer and not die. Many who are suffering greatly still try to hang onto life, and those who would be killed or die suddenly without the chance to suffer still are afraid to die.
• Worry about What Will Happen to Loved Ones – One of the most common fears is what will happen to those who are dependent on us. That is just a waste of time. If you have not made plans to do that, then you should to put that aside. Once you are death, you will not even have any thought of that much less, the ability to do anything about it.
• Isolation. What? You are dead; you are no longer conscious of anything so why make that a reason to fear death?
• Fear of Non-Existence. Another reason to fear death as you would never know it happened. That is an exponentially dumb reason of one is an atheist.
This is merely my theory and a personal reflection, I certainly don't mean to speak for everyone else out there. Personally, I believe human's are afraid of dying not because of a fear of what comes next, but a fear of what all will happen when they're gone. To me, the scariest thought is being forgotten and not having any influence on anything past a certain point. In the end, we are all sentimental creatures who don't want to leave our loved ones.
Particularly accomplishing and achieving things. I want to be all I can be. Death would stop that. I am young but already very conscious of how limited my time is. I agree with the phrase "You only live once" but not in the same spirit others use the phrase. I think "You only live once" so use your time wisely that your life may in retrospect have been worth living, that you may have done something good, to have made a difference in the world.
I don't understand why people who think their life is not worth living commit suicide. That seals it, that dooms that it was not worth living if indeed you are correct about it not being worth living. Whenever I have been afraid my life wasn't worth living that motivated me to put in more effort towards making my life something worthy.
Do something with your life. It doesn't have to be big, flashy, or famous. Do something that will have real meaning and value.