With my 130+ hours of classes in Philosophy dangling 'round my neck like an albatross, I read phrases like "spend eternity" with pedantic fervor.

If one means literally "spend eternity" as a consciousness, then I can only shrug, as I have no sense that my current consciousness extends past my moment of death, so I can treat Heaven & Hell only as linguistic concepts. When I reach the moment of my death (assuming I am aware) I may indeed 'reflect' on my life,: as gnu says "As you are dying, you will be judged. You will be judged by you."
However, I doubt that I must wait until that final moment to have an opinion of how I have conducted my life. At my age, I have thousands of data points to give me a sense of the balance between Heavenish & Hellish parts of my life. I don't feel like I'm close to the end,(who knows?) so I always am able to *choose* stuff that makes me more content with my efforts.
   I guess I feel like even using the terms Heaven & Hell is falling into a linguistic trap that distorts my own attitude toward life & death.

............but you asked. (27 more paragraphs redacted, thus reducing the total blather I could inflict on everyone here. I feel better already.)