I believe that favorite books are designed for re-reading. As many times as you want. My husband chuckles at this and occasionally asks me how many times I've read such-and-such book. Rereading is sometimes like visiting with favorite friends. Sometimes its because I've forgotten large chunks of the story (or information if it's nonfiction). Sometimes it's the comfort of the familiar.
I have a friend from childhood who as a teenager went to see the movie "To Sir With Love," multiple times. I don't even know how many times, but it was more than a few. In those days once you had bought your movie ticket you could stay in the theater as long as you wanted, so it was easy to watch more than once. (And there was ONE screen in ONE theater, so only one movie at time was showing.) I brought this up over the dinner table with my family one night. My father's response was, "She is in a rut." My mother relied, "But it's such an interesting rut."
So what do I reread? Favorite series including Laurie R. King novels, Diana Gabaldon novels, Jane Austen novels, Deborah Crombie mysteries, Dorothy Sayers, Josephine Tey, Jacqueline Winspear, Ben Aaronovitch... I also read books I have not read before!
I also read books that are completely new to me. My daughter recommended "The 7-1/2 Deaths of Evelyn Hardcastle." It is a very intriguing, complicated story. I will probably have to reread that to get all the ins and outs of the plot and characters straight.
Whatever you read, I wish you happy hours of reading!