In my first book discussion, I discuss what I believe happens after The Fault In Our Stars ends. So if you haven't read the book yet & you plan to, I suggest not reading this post, because it is filled with spoilers. Anyways, John Green himself posted on his website that he does not know what happens outside of the text. Here is one thing that he said:
"I have access to the exact same text that you do. I do not have access to any information outside of that text, because then it would just be me speculating about what might happen, and my speculations are no more valuable or authoritative than anyone else’s. Books belong to their readers! Own it! Make it yours!"
I personally love what he has said. I do not think that he ended the story abruptly, and he made it plenty clear in the novel what will happen to Hazel's parents when (and if) she passes. Of course, there are still things that you can't help but be curious about like what happens to Isaac? Does Hazel die? I like how he left that ambiguous. Normally, I get annoyed when authors end their series with unanswered questions and abrupt endings, and then the authors refuse to say what happens. It's like "Are you serious?!" I can definitely relate to Hazel in that respect. I can think of two series right off the top of my head that are like that, but that's not what this book discussion is about. However, like I said, I do not think The Fault in Our Stars ended abruptly. I felt it had a nice closure to it. Obviously, all stories have unanswered questions at the end. Authors can't answer everything at the end of a series or standalone. A book can still have a nice closure, but will still allow the reader to speculate about what happens to the surviving characters. The Harry Potter series is one example. I felt as though it had a great ending, but of course, you still want to know what happens to the characters after the book ends. TFiOS is exactly like that. It had a nice ending, but it leaves the readers with the desire of wanting to know what happens to their beloved characters.
I really like that John Green believes that if he said anything about what happens to Hazel and the other surviving characters after TFiOS ends, that his word would be taken above what everybody else says. He is giving us readers permission to come up with our own continuations, and I love that.
Here is what I believe happens after TFiOS ends: (Of course, this is what I believe. You don't have to agree with what I'm saying, of course. You can have your own thoughts as well.)
Hazel lived at least another year, possibly even longer than that. I don't know if that's enough time to finish her classes at the community college or not. It isn't said how long she's been taking classes before the start of the book. It also doesn't mention how many classes she's taking. I'm guessing one or two. Plus, you also have to factor in all the times Hazel had to miss class when she was in the hospital.
After Hazel came to terms with the fact that while one of them lives, her relationship and love with Augustus while continue on, Hazel noticed a small patch of orange tulips growing in their front yard garden. Her mother swore up & down that she didn't plant them. Hazel realized that it was a sign from Augustus, that he is Somewhere with a capital S, and that he is still with her at all times, watching her from heaven. Hazel then started to believe in an after life. Once she passes, she reunites with Augustus in heaven and she realizes that she was wrong about never being with him again.
I also believe that Hazel & Isaac continued to go to the "Literal Heart of Jesus" meetings with Patrick. Not every week, but every once in awhile. Hazel was able to clarify to Isaac that the girl whom he referred to as having a "hot voice" really was attractive, and he ended up dating her. Isaac also continues to remain NEC for the rest of his life and lives a long life. He eventually marries and has children, who fortunately never develop cancer. He also never gets "robotic" eyes or other prosthetic eyes. He keeps his word on not wanting to see a world without Augustus.
Finally, although it is immensely difficult after Hazel died, her parents continue on with their lives and her mom helps a lot of families in support groups similar to the "Literal Heart of Jesus" groups, and she does so successfully.