As the saying goes, "Love is blind". How is this truly the case with Leo and Stargirl?
Leo is the blind one. He cannot shake off the confines of what is socially acceptable in the average teenaged world. He avoids contact with Stargirl though he is intrigued by her outlandish appearance and behavior. When she changes to become normal and assumes the persona of Susan, Leo is happy. What he doesn't know is that Stargirl is not comfortable with her new life. It leaves her too open to the snubs of American teenagers. Neither Leo nor his classmates can accept the love of all life by Stargirl, especially when that love seems a betrayal of school pride. Stargirl is somewhat blind as well. Her free spirit is too intensely personal for the teens to accept. Belonging to a specific group, not just being a resident of the universe, is a concept that self-centered teens cannot accept. When Mica High School's student body shuns her (and Leo for associating with her), she becomes one of them. In her brief experience of being "normal", her psyche is shattered by the rejection of her peers and eventually Leo himself. All she can do to preserve herself is to leave town and exist as Stargirl in anonimity elsewhere.