Check the content of these to check you’re happy, of course, as some have themes of sex / violence / mental health / suicide / horror
A Clockwork Orange, Anthony Burgess
The Trial, Franz Kafka
War of the Worlds, HG Wells
The Time Machine, HG Wells
The Hitchhikers Guide to the Galaxy, Douglas Adams
The Drowned World, JG Ballard
The Call of the Wild, Jack London
We Have Always Lived in the Castle, Shirley Jackson
The Stranger, Albert Camus
In Watermelon Sugar, Richard Brautigan
Norwood, Charles Portis
Fat City, Leonard Gardener
Things Fall Apart, Chinua Achebe
The Pearl, John Steinbeck
Fahrenheit 451, Ray Bradbury
Catcher in the Rye, JD Salinger
Some more modern options:
We the Animals, Justin Torres
Treacle Walker, Alan Garner
Train Dreams, Dennis Johnson
The Silence, Don Delillo
Mapping the Interior, Stephen Graham Jones
Ring Shout, P Djeli Clark
Eastbound by Maylis de Kerangal
Annihilation by Jeff Vandemeer