80s (probably older) book with technology-powered telekinesis, but with violence as a side effect so using telekinesis required a rite of passage

Question

This was a book I read back in the '80s I believe. Sort of a post-apocalypse setting in the beginning.

It involved a person going into a desert as a rite of passage. She was subjected to hallucinations until a visitor from a colony (comet-based I believe?) arrived, and she realized it was all in her mind.

It ended with the revelation that humanity had created machines (towers) that allowed them to use telekinesis, however the violence that followed caused them to bury the towers in mountains and create the rite of passage as a way of killing off people who failed to learn control. I recall the man "died" in a fight towards the end but was brought back.

For some reason the title "Wandering Star" comes to mind but I think that is wrong.

Answer 1

This might be Watchstar (1980), first book of the Watchstar trilogy, by Pamela Sargent.

From the linked Goodreads:

Alone in the desert, Daiya is faced with dilemma that will determine her fate. If she can successfully resolve it she will join the Net of her village, but if she fails, her life will be spent with the feared Merged Ones. Confused and torn between worlds near and far, Daiya harbors a secret of her people, and must find a way to move beyond her discoveries to a safe place where she can survive

The comet colony and machine granted mind powers are familiar elements from my own search, which ended up being a later book in this same series.