Nothing really happens when we die except to cease to exist. After that no-one can offer a perfect answer to what the purpose for this existence was. But the question is like "why is the colour green, the colour green?". It's a sort of nonsense.
You gain meaning through your life experiences, but these experiences are not pre-ordained and neither do they carry significant consequence. Meanings are made by a person assigning meaning to it; objectively many people see no purpose at all.
How many times have we looked at a cloud and decided that it "looked" like something?
How many times has someone else stated this and we have disagreed?
How many times have we tried to agree on a physical representation of H2O molecules expressed as a vapour in the atmosphere?
This doesn't denounce the beauty of the planet we inhabit but we do not have to suspend reality in order to appreciate it. The universe is magnificent enough without a cosmic force interacting with it, appearing to middle eastern goat herders, demanding flesh sacrifice and generally caring more about homosexuals fornicating in their own home than the plight of African babies.
Derek was a man of clear vision about this world and the absence of the next. That's why he was able to write what he did in his final days. That's where we find beauty and magnificence; a real person facing mankind's greatest fear - the sceptre of death- with humility, honesty, integrity and humour.
He's dead. That phrase does not diminish the man, his deeds or his legacy.
everything is OK