Olivia and Grace are friends even though they have hardly anything in common. Grace describes them as “Introverts. We like doing nothing together. All talk, no action” (8.77). However, they don't really seem to like it all that much. They bicker and fight and stop talking to each other.
One of the main sources of their conflict is that Grace is obsessed with wolves (no matter how much she denies it) and Olivia, well, isn't. She likes taking photos and being close to nature. Grace and Olivia only grow closer when Olivia transforms into something that Grace actually can identify with: a wolf.
Turning into a wolf is the best thing that happens to Olivia. Grace doesn't quite get why Olivia wants to be a wolf. We think we know, and it all goes back to pictures and nature. Wolves, they live in nature. Obvs. But they also think and speak in pictures. Sam says, “It's the only words we have. Just pictures. Just simple little pictures” (24.68). Of course introverted Olivia would prefer this life to a human life cluttered with words.