It's been awhile since I read it, but I have re-read the series with every new book written, and I started at the begining. If I'm not mistaken the wedding happens MAYBE 2/3 of the way into the book (which since season 3-4 are both the book, is not far from where we are), because there is alot that happens to Tyrion and other characters in the wake of the wedding, not to mention the chapters taking place in other parts of the realms.