What is the Monkey King's internal conflict?

The Monkey King's primary struggle is accepting his position as a monkey. While he is described as a deity from the start of American Born Chinese, the gods of heaven refuse to let him enter a dinner party and mock him. This leads him on a quest to gain more power and recognition. With each step, we see him casting aside parts of his monkey nature that caused no problems and, in some cases, were a source of joy when he was simply living with other monkeys. For example, we see him start wearing shoes (and forcing other monkeys to do the same), being concerned with how monkeys smell, and eventually learning to shape-shift so that his form is less monkey-like.
Eventually, the Monkey King meets his creator, Tze-Yo-Tzuh, and is punished for rejecting his nature by being trapped under a pile of rocks for hundreds of years until a humble monk convinces him to return to his original form. Here we see one of the primary themes of the book: the importance of self-acceptance even in the face of marginalization.