And as to expand on "The matter is not annihilated, merely transformed.": You have matter(mass + volume) of which you transform the mass into energy, and you are left with volume but no mass and since a "something" without both mass and volume is not matter anymore, the matter "ceases to exist" which can be misunderstood, but merely means that you have taken the mass away and what is left cannot be defined as matter anymore. It is not, in fact, annihilated.
There we go, transformation is the key.
Nothing ever ceases to exist(die) it just transforms(evolves or deliberate changes turns it) into something else.
This is the basis of all life i think.
