Question: Does Salem ever become human again?
Chosen answer: No. In the show he was sentenced to 100 years as a cat and only served 25 years at the time of the pilot (all episodes of him being human are flashbacks). The comics did several retcons to change Salem's backstory to fit the show's, and as of 2015, he was still a cat.
Question: I watched the show for a while when Sabrina was in high school, and then I stopped. I recently saw an episode, where Sabrina was living in her house and her aunts were gone, but she was living with two other girls. Who are those girls and where did her aunts go?
Answer: Those are her roomates. The first season Sabrina was in college, she moved out of the house that she shared with her aunts and she moved in with 2 girls plus another guy. I think her aunts went back to the other realm since the 2 actresses (Caroline Rhea and Beth Broderick) who played them left the show. The guy roommate also left the show the same time as Sabrina's Aunts. Then Sabrina and her roommates moved into the house.
Hilda got married and Zelda became 8 years old again so that Sabrina could have her live life back.
Question: Is Miles even alive? He was cut from the show with no explanation, after he found out Salem wasn't a real cat. Then, in season 7, it was reported that somebody with his surname was shot.
Answer: In the S6 E18, "I, Busybody" Salem got permission from the Witch's Council to be human for one day to meet his pen pal, Roxie. It was all a point of view camera shot.