It looks as if I was able to search out what you were looking for: One or more parts of A.A. Attanasio's Radix Tetrad, particularly The Last Legends of Earth.
A few thousand years ago, an intelligent being from a reality we never suspected found our dust. For its own alien purposes and by its own strange science, that intelligent being read in our dust the cryptarch of our lives (the fossilized DNA sealed in pebbles of the shattered Earth by the heat of the exploding Sun). From our cryptarch, the alien created us again. And not just our bodies. You remember Earth, because this alien intelligence retrieved your Consciousness from the vacuum, where the wave pattern of light emitted by your brain had been expanding at the speed of light since you died.
The Last Legends of Earth happens billions of years in the future. Although humanity died out, humans are brought back as part of a war between two races called the "Rimstalkers" and the "Zōtl". As per Wikipedia:
The primary character is a young female Rimstalker named Gai. She is assigned as the Mission Commander to lure the zōtl spiderfolk with intelligent life as food and also to find an artifact (the O'ode) in order to kill the zōtl. Ultimately, humanity is brought back from the dead as bait for the zōtl. Gai and the few soldiers who are left after the zōtl attack on the Rimstalker's world have been sent out to create artificial star systems and re-created intelligent lifeforms found in the dust of intergalactic space in order to lure zōtl.
This matches your description of humanity re-created by an alien female, and of course the giveaway clue about "Rimstalkers".
The book is divided up by "Age", in which notable events accrue. Gai discovers a human which has been flung back from a distant time "Age" in which she is victorious. After aiding this human to try to find his lost love, She decides to track him and follow him to ensure that her future is same as the one he came from.
The story builds on multiple short stories of people and events that occur in these various time periods.
This matches your description of the episodic nature of the story, and Gai's interest in a particular young male human, named Ned O'Tennis, whose search for his soulmate Chan-Ti Beppu is a thread holding the whole story together.
The other three books in the Tetrad are very different in plot and characters so they are unlikely to match other pieces of your question. But there's only one way to find out....
: It took me FIVE MONTHS to read The Last Legends of Earth
! This dense, complicated book of cosmic scope was exhausting
to read, and I sometimes went a week or more without picking it up. Then insomnia caused me to read the last 100 pages in one sitting.