Pre-life and post-life are logically identical. In other words, being dead is exactly the same as not being born yet.
Unless you mean spiritually, you are wrong. If you are dead, you exist, physically but you don't exist physically when you weren't even born.
Life = Moment of time when you are alive, therefore Death = Moment of time when you aren't alive anymore. So, we won't live forever.
Life != existence