I think one of the worst things Diane ever did, that she never got called out for, was using Penny’s story as a plot point in Philbert, just to rip Bojack a new one. I do understand he needed to be called out since he hadn’t really faced any real consequences for it yet, but making it into a plot point in a show that aired publicly was a shitty thing to do. Yes, the circumstances in that story were slightly different, but on the off-chance Penny or her mother happened to see that, it’s her trauma being aired without her permission. That wasn’t Diane’s story to tell and if she really was that angry about it and so determined to go after Bojack, she should have done it differently. I also hated the reporters who pried so hard into Penny’s story without any regard to how it would affect her, but they were already established as shitty people who didn’t care at all. Diane knew better and still did what she did.
I just got so angry about this and had to vent. I get why it happened, but I still hate that it happened and that no one called her out for it once they all learned about what Bojack did. Not that I can think of a way they would all find out it was her that made that plot point in the script, aside from maybe PC or Bojack connecting the dots since they were there for it.
Diane makes everything about herself. She is totally self-absorbed, and never really gives consideration to anyone else’s feelings or experiences. That’s established from the very beginning, when she’s hired to ghost write someone’s autobiography, but instead writes a book all about her experiences with that person and puts her own name on it. And then leaks part of the book to spite him for calling her out on not doing what she was hired to do.
So of course, when she hears about what Bojack did to Penny her reaction was not “how could you do that to her?!” it was “how could you do that to me?!” And she proceeds to yet again use the access provided by her position as a writer for spiteful purposes. What happened to Penny meant nothing to Diane beyond how she wound up looking like a hypocrite for supporting someone who would do what Bojack did, after all her self-righteous and judgmental posturing. That’s why she felt “betrayed” by him.
It never even occurred to her, when she sat down to write that scene to lash out at Bojack, that she was exploiting a vulnerable young woman’s trauma for spite. That is a truly repugnant and disturbing display of main-character syndrome. And she hasn’t changed much by the end of the series.