Forgive me. It is utterly appalling that anyone should have to read a book review that begins like this. It really is. But there is just no shying away from the fact that Abby Horne, the 30-something protagonist of Jordan Prosser’s latest novel Blue Giant, desperately needs a good hangover shit. It has been weeks since she last had a bowel movement and there are only so many bottles of Yellowtail Cabernet Sauvignon a tactless, crude, self-absorb…