“5. Man has a natural desire to live forever.”
That sounds more like wishful thinking than a proof.
I agree. Not everybody wants to live on for an eternity.
Most people do make efforts to prolong their lives and flee death, as well as yearn for ways to make their lives meaningful and memorable to others. But there are a handful who would consider this merely to be raw instinct brought about by a felicitous collision of matter. The biblical texts, properly understood, shed a great deal of light on what otherwise is more difficult than seeing through a mug of stout.
being separated from family and friends through death usually upsets everyone. Living here with disease and evil, no thanks. Being with loved ones, in love, joy, and peace plus being with God where nothing we know now applies (new science) sounds like fun to me.