I haven't ever picked up a Star Wars book and read it but I have done quite a bit of reading on various subjects every time I watch one of the movies. One thing that has been bothering me is
Luke leaving and going into hiding in The Force Awakens.
Of course we won't know the real reason he did this yet but I am questioning the fact that he did it and not the why.
When Yoda and Obi-Wan do it, it's because the Sith have taken over everything. They can't fight an entire army by themselves. But for
Luke it's different. He has the entire New Republic on his side. Yes, he failed with Kylo, but that was a mistake. Leaving and going into hiding while a war is slowly waging on is a choice.
And a very un-Jedi one at that. There is a point in the 3rd movie where Yoda says to Anakin
YODA: Train yourself to let go of everything you fear to lose.
We find out that Luke made a mistake and for some reason left to go find the first Jedi Temple. We can only speculate why he did this but what reason is good enough to thousands of people to suffer during his exile? Is this just because of how informal and short his training was as opposed to someone like Yoda/Mace/Obi-Wan/any other Jedi Master? I can't see any of them abandoning their duty like that.
Edit: To clarify a bit, my definition of the Jedi would be that of the Jedi Order with the members of the Jedi council representing the epitome of a Jedi. Anyone can follow the force (as I understand it, the Force isn't good or bad, it's how you use it that matters) but not everyone using the Force has to be following the ways of the Jedi.
He is wallowing in guilt and maybe even doubts himself.