here), then what happened once can happen again.
For the Time Traveller, his experience of the end of life on Earth (see here) is not his last experience precisely because he is a time traveller:
"So I came back...The blinking succession of days and nights was resumed, the sun got golden again, the sky blue."
-HG Wells, The Time Machine (London, 1973), Chapter 15, p. 95.
For such literary expression of sf ideas, I think that Wells' principal successor is Poul Anderson, whose Martin Saunders travels beyond the end of life on Earth to the end of the universe, then beyond that:
"...there was nothing but the elemental dark. Entropy had reached a maximum, the energy sources, were used up, the universe was dead.
"The universe was dead!"
-Poul Anderson, "Flight to Forever" IN Anderson, Past Times (New York, 1984), pp. 207-288 AT Chapter Six, p. 284.
However, five paragraphs and billions of years later and after Saunders has eaten a sandwich inside his time projector:
"The universe was reforming." (p. 285)
Anderson's heroes usually find something to hope and strive towards. After his previous accomplishments, Saunders just has to keep moving forward.
The alternative endings shown to Artos (see here) were edged out of previous cycles into implausibility by the Goddess - straining comprehensibility.