I am so sorry for the family’s loss. It’s hard to imagine death being nonexistent. May you find comfort however, from the future promise recorded in 1 Corinthians 15:26 which says “the last enemy, death, is to be brought to nothing.” This is a promise from God and we can be certain that he will fulfill his promises. May you also find comfort from Revelation 21:4 which says “he [God] will wipe out every tear from their eyes and death will be no more.”