What is the possibility charlie doesn't want to think about in flowers of algernon?

In "Flowers for Algernon," Charlie Gordon struggles with the possibility of losing his newfound intelligence and the relationships he has developed. He fears returning to his previous state of mental disability and being unable to connect with others, particularly with those he has grown close to, like Alice. This fear highlights the fragility of his transformation and the emotional turmoil associated with his identity and self-worth. Ultimately, Charlie grApples with the painful reality that intelligence does not guarantee happiness or fulfillment.