As far as King of the Hill goes, she probably just came to the studio and recorded all her character's lines for that season in one day and received her check. It's not nearly the same as a sitcom with long days, multiple takes and interactions with your fellow cast mates.

The sun is shining but the ice is slippery.

Lifetime are know for being over-dramatic, even melodramatic. Every single program is women screaming, crying, yelling, throwing stuff.
Don't know what you were expecting from it, really

They leave out part where she move here make new life.

Because Im happy
Clap along if you feel like a room without a roof
Because Im happy

I was looking forward to a movie showing how she got to where she was in the industry and what she had to overcome to get there rather than an over dramatized movie mostly about her husband and her self esteem issues.
It's Lifetime, so I really don't know what I was expecting.
http://pink-nightmare.com
sarcasm & stories

Wasn't she also engaged a couple of times in there too?

I don't recall them talking about Girl, Interrupted either. I think they did allude to Sin City as that movie she didn't want to do but did anyway.

Oh that's right, they did skip on Sin City as well! Also one of her top credits shunned completely.
All they did with reference to 8 Mile was a quick scene with a reporter at a premier asking questions, and Brittany saying Marshall was a great actor. That was the extent of that.
Good point MJ_Dangerous. They did add a lot of unnecessary filler to dramatize it more.

They skipped over King of the Hill and Sin City. Did they mention 8 mile?

I agree. There were a couple movies I was surprised they didn't cover. Not to mention that a good portion of the movie focused on the "drama" surrounding her husband. I honestly didn't even find it necessary to mention such a thing in a movie about her life. Personally, it was the most uninteresting part for me. The movie seemed tabloidish. I'll admit, I don't know too much about Brittany Murphy, but I'm familiar with a good bit of her work. Regardless, I could just tell the movie wasn't accurate or honest. And I doubt that was the purpose anyway. Sadly, when celebrities pass away, especially at a young age, everybody wants to cash in any way they can. In that case, the truth and accuracy is never the way to go.
"It is better to fail in originality, than to succeed in imitation."- Michael Jackson