That's just it - Meyer only left us with one day or so to tell the story of Bree. I know this was just a rough sketch she doodled out, but if she was going to publish the thing, couldn't she be bothered to expand it?

"Just why does she come across as so misanthropic in her books?"

I noticed the same thing, and I almost wonder if Meyer has some issue with connecting to people. Like she immersed herself in how humans would look to a vampire, and somehow didn't realize that it makes her characters foreign and impossible to relate to.