I like that you had the courage to express empathy for the shooter. Not many people are willing to do that.
It's all too easy to write off shooters as monsters or evil. Some are, maybe. I don't think most are, though. They're humans (usually with a mental illness) who were pushed to a point of desperation.
As far as I'm aware, she was the only casualty. Thankfully no one else died. If she had used anything else other than a gun, then people would probably empathize with her. She had an emotional breakdown and killed herself, after wounding others. While I don't condone her actions, I can't help but empathize with her, no matter what others might think.
The reality is that humans are emotional beings and we can break, easily. Modern society doesn't want to acknowledge that we aren't perfect anymore. If acknowledging that humans have faults and empathizing with those that fail makes me weird, then I'm weird.