If someone breaks the law by posting something online, then it's going to be rape threats, or seriously horrible personal attacks. Why would I feel sorry for someone who thought they could allow their hidden spitefulness out to play without any chance of being identified, when they found they were wrong? I don't feel sorry for those trolls jailed for making rape threats, either.
Online venom on this scale is a form of abuse. The anonymity allows people a sense of power, because the victim hasn't the first idea who they are dealing with and will inevitably worry away at it. It's very different to the sort of bullying you see on MN sometimes (not that that is edifying, but it isn't maliciously targeting someone with the sole intent of causing harm - it's genuine, if overly invested, disagreement). It's a form of harassment and abuse.
I'm sorry anyone feels they have no option but to take their own life, but it seems to me that this woman basically liked being nasty to people, and only social pressures and the desire to be respected and liked stopped her. Online, those pressures were absent and her true self came out. I do feel sad she felt she had no options left, but plenty of people are hurt and humiliated by the media who haven't done much, if anything, wrong. She had. The media didn't make her post those things to a pair of parents suffering unimaginably. She chose to. She then couldn't bear the thought of people knowing about it.
The net is a lot less anonymous than people seem to think it is. And I don't think that is necessarily bad, either.