Other than the two insiders in this thread, who are giving us some insight into Jameel's thought process, the rest of us are making wild guesses.
Here's my internet psychologist theory.
Jameel has been struggling more and more to accept that the NBA is not going to happen. He has spoken candidly about his NBA goals, and has clearly worked extremely hard towards trying to achieve that goal over the last few years.
However, this season it became increasingly obvious that he's not going to the NBA. What he hoped would have been a season where he lessened his weaknesses, he has only lessened his strengths. And his weaknesses have remained.
As the season has progressed, he's realized that he is running out of time, and this has led to a lot of desperation, frustration, and disappointment. The fans have been blamed. The city has been blamed. The coaches have been blamed.
I'm still hoping he can fix things this season, and be the player he was last year. Unrealistic, I know.