He started down the path to become a Jedi because his foster parents were burned alive. Then his mentor committed suicide right in front of him to become one with the Force. Then he became a pawn of Yoda and Kenobi in order to defeat two evil Force users. So he trains to become a Jedi and finds out that his old mentor and his new mentor have been lying to him about who his father is, and want Luke to kill his father anyway. So he confronts his father and risks his life in other to bring him back to the Light (which, according to his lying mentors, is impossible). But despite all odds, he succeeds, but sadly he only gets to spend 10 minutes with his father before he dies. So Luke saves the galaxy and is instrumental in balancing the Force.
He then starts to rebuild the Jedi Order. He starts a school just to have it wiped out when one of his students goes dark and kills all the students.
At this point (TLJ) he has every right to be like "WTF Force? I've done everything right and you still sh!t on me." Then Rey shows up and wants to be trained... Can anyone blame him for telling her "Noooooooope!"?
>>83847100
>implying Disney puts this much thought into character motivations
Of course. >>83847253
Disney's Star Wars is shit. Prequels are kino.