“Abby turned to Gretchen and smiled and her stitches ripped and her mouth filled with salt. But it was worth it when she turned and saw Margaret Middleton standing there like a dummy with no comeback and nothing to say. They didn’t know it then, but that’s when everything started, right there in Mrs. Link’s homeroom: Abby grinning at Gretchen with big blood-stained teeth, and Gretchen smiling back shyly.”

Throughout My Best Friend’s Exorcism, the narrator often remarks on things that the characters don’t notice or realize. This develops The Complexity of Friendship because friendship often defies characters’ expectations, such as Abby and Gretchen’s “small” moment in this quote—which leads to a 75-year-long friendship. Friendship is also complex in that Margaret, a bully to Abby and Gretchen, later becomes their friend in high school.

“Mostly, for six years, they stayed in Gretchen’s room. They made endless lists; their best friends, their okay friends, their worst enemies, the best teachers and the meanest teachers, which teachers should get married to each other, which school bathroom was their favorite, where they would be living in six years, in six months, in six weeks, where they’d live when they were married, how many babies their cats would have together, what their wedding colors would be.”

The novel challenges the idea of blood ties through the complexity of friendship. Here, Abby and Gretchen fantasize about the future, but the focus is not on spouses and children, but their continued friendship—the things that brought them together and will continue to do so.

“‘You’re selfish. I’m the fun one, and you’re the mean one.’

They were always trying to figure out which one of them was which. Recently, Abby had been designated the fun one and Gretchen the beautiful one. Neither of them had ever been the mean one before.”

This quote complicates the complexity of friendship and The Mercurial and Relational Nature of Identity. Abby and Gretchen are such close friends that their identities tend to bleed together, so it’s not always clear where one of them “ends” and the other “begins.”