I would tell the ones I love that I love them, and I would simply... chill (would be better if they were to be by my side). It's the end of the world, anyway. Why would you stress about it when things are coming to end? Might as well just make the best of the few hours you have left. And maybe, just maybe, we would meet again in the afterlife. I believe in souls who genuinely care for one another would cross paths in any world they live in.