In response to those who think Hannah overreacted about everything

This is an article that explains the teenage brain using neuroscience. (not totally sure how to do links here)

http://www.theglobeandmail.com/life/parenting/drama-queens-whats-really-going-on-in-a-teenage-girls-head/article28549947/

If TL;DR
'Updates to the limbic system heighten the brain’s emotional reactions with research indicating that the feeling centres beneath the cortex are actually more sensitive in teens than in children or adults. For example, one straightforward study used functional magnetic resonance imaging to watch teenage brains respond, in real time, to emotional input. The research team showed images of fearful, happy and calm faces to children, teens and adults while monitoring the activity of the amygdala, a key player in the emotional reactions of the limbic system. Compared to the brain activity of children and adults, the teens’ amygdalas reacted strongly to fearful or happy faces. In other words, emotional input rings like a gong for teenagers and a chime for everyone else.'

This explains why the nicest butt was such an issue for Hannah. Now obviously everyone's brains and brain development are not exactly the same and there are other things to contend with. But I don't find Hannah's reactions all that uncommon. There was another post that commented that they took the mental illness aspect away from the suicide, but I will counter, who in high school knows that their friend may be mentally ill? Depression has many facets.

No, Hannah is not the most sympathetic character, nor do I think that she was meant to be.

This is an older study that was done on the development of the brain and also includes hormones, puberty, neuroscience, and external circumstances. http://www.mdedge.com/currentpsychiatry/article/62670/teen-girl-brain-high-drama-high-risk-depression