Well I think the reason it doesn't make sense to you is that you think death means death. However, if you read the scripture you shared...
Genesis 2:7
Then the LORD God formed man of dust from the ground, and breathed into his nostrils the breath of life; and man became a living being.
You have to ask yourself this question....Where does that breath go after you die? Now if you say that breath is just oxygen (and other things) that returns to the atmosphere, then we have already found our disagreement. For that breath is more than just oxygen. If we give God the credit for that breath of life....then what is it? Where does it go after death? It goes back to God because its a form of energy that only He can share, which can not be destroyed...however, it can be transformed.
If you are part of the family of God, you will be transformed into a glorified body one day...if you are not part of the family, you will just be in that post death form of energy. That energy is actually a part of God. Not in the sense that the person is "filled" with the Holy Ghost, but is made in the image of God. It has value because of being in His image.
Perhaps mankind has gone overboard with images of devils with horns and pitchforks, but separation from God is for sure. They will want to die, but can't.