Alive and Well and On a Friendless Voyage by Harlan Ellison (F&SF, July 1977) is the second story in a special Harlan Ellison issue of F&SF, and begins with a man called Moth coming out of his cabin on an exotic spaceship and into the lounge. There, he goes from table to table talking to different groups of people (“this ship of strangers”) about various traumatic episodes from his life.
The first of these sees Moth listen to a couple who tell him not to blame himself for letting his child die; then he talks to an abusive and unsympathetic young man about a younger partner who cuckolded him; in his next conversation he tells a woman about how he failed to intervene in a fire in an old folks home; and then he reveals to a fat man how he took a female employee away from her husband and child (and how she later committed suicide).
There are a couple of more confessionals before he tells a woman that:
“I’ve come to realize we’re all alone,” he said.
She did not reply. Merely stared at him.
“No matter how many people love us or care for us or want to ease our burden in this life,” Moth said, “we are all, all of us, always alone. Something Aldous Huxley once said, I’m not sure I know it exactly, I’ve looked and looked and can’t find the quote, but I remember part of it. He said: ‘We are, each of us, an island universe in a sea of space.’ I think that was it. p. 36
At the end of the voyage all the passengers disembark except Moth, who asks if anyone wants to take his place for the rest of the metaphor voyage. No-one volunteers.
I’m not a fan of existential mopery, but this is probably a reasonably well done example if you like that sort of thing. (At least the navel-gazing here is mostly about traumatic events and not the more usual—for the current SF field— boyfriend, body, parental or petty political concerns.)
** (Average). 4,100 words.