The phrase "had it" is typically used to express a sense of finality or exhaustion, but there are a number of synonyms that can be used to convey this sentiment in different ways. Some possible alternatives include "at the end of one's rope," "fed up," "worn out," "at one's wit's end," "at the breaking point," "done for," "over it," "had enough," "maxed out," "exhausted," "spent," "drained," and "finished." Each of these phrases carries its own nuances and connotations, offering a wide range of options for expressing a sense of frustration, fatigue, or resignation.