This is a defensible thesis topic and a table of contents could cover the ways the creature becomes gradually more aware of his rejection by his creator and his society and how these various elements feed his rage. A table of contents could cover the following:
I. Rejection by the father: Victor abandons and flees from his creation—his child—at the creature's birth at his hands. When they meet on the mountaintop, the creature speaks to Victor of some of his hurt and rage at this primal rejection.
II. Rejection by good people: The creature, having learned it is rejected, feared, and despised by the wider culture, hides in the woods, observing and anonymously helping the De Laceys (such as by gathering wood for them) and learns much from them about society and family life. He also learns to read by watching them. Yet when he reveals himself to them, even these good people are terrified, and Felix attacks him. This anguishes the creature.
III. Rejection for doing good deeds: The creature saves a boy's life and is shot in the arm as thanks.
IV. Forced isolation: The creature's heartfelt request for a companion to help him bear his loneliness is rejected when Victor tears apart the bride he has created for him, fearing a race of monsters would be born.
V. Books provide a paradigm for understanding his rejection: When the creature finds a packet of books, he reads them. Milton's Paradise Lost provides a model for his own rejection. Like Satan, he decides to strike back at his creator—unless he is helped by him.
With the TOC in hand, it becomes easy to see the total rejection Frankenstein's creature has received for simply and good-heartedly trying to find the acceptance and community every human being craves—rejections that have turned him into a rage-filled monster. He is a relatable character because any of us, faced with such heart-breaking and otal rejection, would become enraged and want to strike back against those who hurt us. Frankenstein is more human than those who encounter him want to accept.