Death is no relief

I don't know what would be worse - continuing in this life, or ceasing to breathe. I don't say "die" or "ceasing to exist" because I don't know if dieing would allow me to cease to exist. I have this horrible nightmare that if I suicided I would end up with none of the five senses, alone with my thoughts, through eternity. That would certianly be hellish. I also fear that if something doesn't change within me before I die of old age, that might also be my fate.