Cory Monteith's death could not make Lea Michele less of a diva bitch. With the help of Glee's co-creator Ryan Murphy, Lea managed to ban Dianna Agron from appearing in the Cory Monteith Glee tribute. From Radar:

“It’s shocking, because even though she’s not contracted for this season, many other actors returned to pay tribute to Cory…even ones with less of a story connection to Finn than Diana had!” the source told Radar.
“Remember, she played his GIRLFRIEND on the series, and was a major part of his storyline.”
The insider reveals that Monteith’s girlfriend, Lea Michele, and co-creator, Ryan Murphy, “intensely dislike Dianna and have both worked to marginalize her as much as possible.”
“They never saw her as a team player,” the insider added.
“They simply did not want her sharing the glory for this very special episode.”

Putting their differences aside, the show just wouldn't be the same without Agron in it. But now we know why it was so difficult for the Monteith to stay off alcohol and drugs.


Image: Ryan Murphy and Lea Michele