Seneca quotes Epicurus as bidding us to think of death. He goes further to claim that it is a wonderful thing to learn thoroughly how to die. To think of death, he says, is to think on freedom.
Life long learning amounts to nothing. You get no credit for actions taken casually, even if these are momentous and consequential. An examined life, one of reflection and action that changes your habit, the habit that becomes character, the character that seeps into the crucible of your soul: that is all you get credit for.
If that leaves a wonderful legacy in the world, a fortune, a place in the heart and memory of others, you are lucky.
If your endeavors and your passions leave no mark in this world and no one knows of your soul's work, you can not have regret. "I leave no trace of wings in the air, but I am glad I have had my flight." Tagore (Fireflies)
Of all the billions who have lived, the sentient creatures who walked the earth, and looked at the stars and wondered of their brief time on this speck, you are one of them. That should be lucky enough. Gratitude for our existence should help us think of death - and our freedom.