Do some reading in this thread and see if it puts things into perspective: http://www.metafilter.com/85667/Hi-Whatcha-reading#2777344
After realizing that, yes, this stuff happens to women all the time, it's not hard to extrapolate this behavior to the internet, where people are bigger targets and harassers are even more anonymous.
She was a woman on the internet. That's all the reason they need.
Another way for it not to seem odd: Go read the book "Why Does He Do That?" by Lundy Bancroft. [1] (If anybody would like a copy, just contact me via email and I will send you your choice of paper or Kindle versions. I've given 12 away so far.) It's a book by a fellow who spent 15 years as a counselor in a program for abusive men. If you read that, then it's pretty clear that there are a lot of men out there who want to abuse women.
My take on a lot of this behavior is that the Internet, in connecting everybody to everybody, has connected a lot of would-be abusers to lots of women. Previously, they would have been sad and alone in their basements; they wouldn't have anybody to harass. But now they can mob up and attack women jointly.
[1] http://www.amazon.com/Why-Does-He-That-Controlling/dp/042519...
Sadly most people seem not interested in the psychological or sociological motivation of those abusers. There is always something that triggers abuse (no, I am not saying that it must be something the victim did). I wish we would investigate into that and help people stay clear of the psychopaths that way.
http://seriouspony.com/trouble-at-the-koolaid-point/
"I now believe the most dangerous time for a woman with online visibility is the point at which others are seen to be listening, “following”, “liking”, “favoriting”, retweeting. In other words, the point at which her readers have (in the troll’s mind) “drunk the Koolaid”. Apparently, that just can’t be allowed."
Read the whole thing, it's heartbreaking and eyeopening. It also involves some of the same people that attacked the author of the current post.
So whatever these two woman did to "incite" this harassment was shared by at least two kinda-succesful woman in tech.