It sounds like you are at the same spot as I am, which means I asked this question a month or so ago.
According to Stephen King, in his book On Writing, you should put your story away, until you can "look at it with fresh eyes". He says that a minimum amount of time for this is six week, but six months is not unreasonable. As luck would have it, I hit six weeks of "trunk time" today.
Mr King also suggests working on a draft or an edit for another project before going back to this one. He says "preferably something short."
I am thinking that you have to leave the book in the trunk until you stop really, really wanting to take it out.
As for a good book on revising and editing books, I just asked that question, and the answers I received were Self Editing for Fiction Writers by Renni Brown and Dave King, which received excellent reviews by the writers on this board, The First Five Pages, By Noah Lukeman, which received mixed reviews, Eats, Shoots and Leaves by Lynne Truss which received mixed reviews, and Manuscript Makeover by Elizabeth Lyon, which received a single recommendation, but a positive one.
I should note that there is a review of Makover on the Amazon page that favorably compares it to Self Editing, without mentioning Self Editing by name.
Hope that helps,
Dave