They don't even bother giving these movies legit plot summaries anymore. Basically, there isn't one. This is literally a "you read the book so you are going to see the movie" franchise. This one was really nothing more than a three scene set up for the second part. They get married. They go on a honeymoon. She has a baby. That's it. Seriously. I was pretty bored by this one. Definitely more so than the previous three installments. But none of that matters because if you love the story - you love the movie. If you don't - then you don't.
Like I said - my recommendation really doesn't matter whatsoever. You either live for this "story" or you have no interest whatsoever. I felt like it was just a set up but Part 2 really won't make much sense without this three scened movie.