Julie of the Wolves by Jean Craighead George

"To her small village, she is known as Miyax; to her friend in San Francisco, she is Julie. When her life in the village becomes dangerous, Miyax runs away, only to find herself lost in the Alaskan wilderness.

Miyax tries to survive by copying the ways of a pack of wolves and soon grows to love her new wolf family. Life in the wilderness is a struggle, but when she finds her way back to civilization, Miyax is torn between her old and new lives. Is she the Miyax of her human village—or Julie of the wolves?"