My advice would be to read the first 2
What story do I tell you?
I loved the first 2 books. I couldn't put them down.  I could barely get through this one. The story was repetitive and boring.  I don't know why Roth decided to take the book the way she did. All I can think is that the up coming movies swayed her decisions.My advice would be to read the first 2 and make up your own ending.  This one will only disappoint you. 