The Torah Temima questions the Midrash brought by Rashi, regarding Dina. It is written that Yakov was punished because he hid Dina in a box, so that Eisav would not see her.
He goes on to explain that if Dina would have married Eisav, she would have influenced him, to mend his evil ways. Because of this “sin,” the incident with Shechem took place, when Dina was violated.
It seems understandable why Yakov would not want to take a chance with the match between his daughter and his brother. Eisav was evil, and wasn’t there the possibility that she would be influenced negatively by him.
The תורה תמימה goes on to explain where Yakov errored. There was no doubt that Dina would have succeeded in changing Eisav, and Yakov knew this. The matter became personal, in the sense that Yakov didn’t like Eisav very much, either. He let his own feelings take precedence over the possibility of reforming his brother.
This is why Yakov was punished so severely. The expectations of a great Tzaddik are great. He should have risen above his own personal feelings, and saved his brother. It is not always easy to do the right thing. The greater the person, the greater the expectations of him.