By the fourth and final season, Clay has a full mental breakdown as a result of a combination of troubling factors. ... These therapy sessions finally provide us with some answers about what's going on with Clay. He confirms that he's suffering from anxiety and that trying not to feel anxious just makes things worse.

Does Clay have a mental illness?

Despite these troubling moments, Clay is never explicitly diagnosed with a specific mental illness — something experts took issue with last year when it came to the portrayal of Hannah's suicide.

Does Clay go insane?

By the fourth and final season, Clay has a full mental breakdown as a result of a combination of troubling factors. Not only does he routinely have intense nightmares featuring the now-deceased Bryce and Monty, but he also hallucinates them during his waking hours.