Going one's rocker means losing one's mind or sanity. Some synonyms for this expression include going nuts, going crazy, losing it, going bonkers, going insane, and going off the deep end. These are all idiomatic expressions that have been used to describe unusual, erratic, or irrational behaviors that are typically associated with mental instability. Other synonyms that are less commonly used include going mad, flipping out, going berserk, losing one's marbles, and having a breakdown. Regardless of the expression used, they all refer to a period of time when a person's mental stability is compromised, and they are behaving in a way that is not typical of their usual self.