Question: does buffy's mom come back to life

Answer: No, Tara realizes that A History of Witchcraft is missing from their shelf and after concluding that Dawn took it, she and Willow (who is sheepishly feigning surprise) decide to call Buffy. Buffy hears about Dawn's spell just as she is finishing it upstairs in her room. When Buffy confronts her, the two girls get into a vicious argument about their different ways of dealing with their mother's death. Dawn accuses Buffy of being so busy arranging everything that she doesn't care that their mother is dead, earning herself a slap across the face from her sister. Buffy immediately regrets her action and admits that she's keeping busy so she doesn't have to deal with the situation, because when she stops then her mother is really gone. During their argument, a figure emerges from Joyce's grave and walks toward the house. A shadow passes by the front window followed by a knocking on the door, and Buffy, hoping it's Joyce, rushes to answer the door. Dawn immediately realizes the inherent dangers of the spell and rips up the photo, and when Buffy answers the door all she finds is an empty step. This is too much for Buffy and she starts to cry, finally facing the reality of her mother's death. A sobbing Dawn hugs her, and they collapse to the floor united in grief.