I read this book in the 70s or 80s. It was titled something like “The girl, the witch, and the cat” or something. I really only remember that the title had a list of 2 or 3 things and said witch. It is not the lion, the witch, and the wardrobe. I believe there were 3 books in the series. It was about a girl around 12? who befriends a kooky old lady who turns out to be a good witch. The 2 become very close, like family. I believe the girl is an only child. There may also be an old warlock who is friends with the old lady. One part i remember is there is an old friend of the lady who tries to kill or put a spell on her. This results in the girl having to drive the old lady’s car to help save her. When she looks in the rear-view mirror she sees glowing eyes in the backseat; knows this is the bad lady. Somehow it all turns out good. It seems there may also be magical items such as a bowl, a phoenix, the cat, etc. Though I may be mixing those up with another beloved lost story.