Josh and Lety didn't know each other very well throughout high school (and still don't know each other very well today).
When Lety didn't know someone, she tended to assume things about their personal life based on very general stereotypes.
Because Josh liked rock music, had piercings, and wore band tees and basketball shorts, Lety concluded that he did drugs and fuked a different girl every weekend.
She didn't mean it as a joke or throwaway comment. She truly, in her heart of hearts, thought that that was Josh's life and was shocked when Jared told her it wasn't.
In fact, Josh had never done any drugs at all and only had long-term relationships. ❒