My first question is "How old are you?" I am 57.
I have felt many of the emotions and doubts you described, about death.
I was brought up in a nice, albeit religious family. I tried to believe in the existance of a perfectly benevolent god, but found too many inconsistencies between biblical teachings and reality as directly observed. I have settled for a multi-pronged approach to looking at many of the major issues, such as death and afterlife. How about if I share my views on the last issue?
If there is an afterlife, as most religions claim, which one is right? I think this is too divisive for a perfectly benevolent deity to set up, so I reject it as sectarian propaganda.
Perhaps a perfectly benevolent god would have a well thought and executed afterlife for all, regardless of their sectarian belief system. I could accept that if such be the case.
Is there a heaven or hell? Please note that I use these terms in a non-sectarian meaning.
I could accept the existance of a heaven, because a perfectly benevolent god would likely create such a place. But such a god would not need to create a hell. Simple oblivion would suffice.
so, to summarize a long-winded explanation, Heaven or Oblivion seem equally likely, but Hell is antithetical to a perfectly benevolent god.

Logically, an atheist simplifies this matter by believing in Oblivion for all.
Over-all, I've stopped worrying about the afterlife or the lack thereof.
Sectarians believe I'm going to Hell, although my personal ethics and morals are stronger than the majority of the ones who believe they are "Saved" and headed for Heaven.
Non-sectarians mostly believe I'm headed for Heaven, while the rest believe I'm headed for Oblivion.
Agnostics, like myself don't have enough data to lean one way or another between Heaven or Oblivion, so it is the whole Schroedinger's Cat debate all over again.