One thing I noticed...

I agree.

Good observation. I also think Joan sabotaged her own happiness because a part of her felt like she wasn't worthy of it. I read something about her childhood and how her own mother was cruel to her and blamed her when she discovered her husband (Joan's stepdad) had been raping her since she was 12 or 13 and she looked at Joan as "the mistress" and not a victim. Instead of choosing to do a better job at being a mother she chose to adopt, control and abuse her own kids like punching bags whenever the shame and pain from the past came back to haunt her.

It was a movie, not real life. Yes, Joan was a bitch and should've NEVER adopted Christina & Christopher, but what you are watching in this movie was written by a screenwriter. It isn't word for word what Christina said happened. Also, we also have one woman's word over another. Joan never got to defend herself. Try reading some comments from people who used to work with Christina in the theater. She was bat shit nuts and constantly lied & exaggerated.

Well, the movie concentrates on her explosive episodes. A person just sitting there being happy is not considered good entertainment.