Having looked with disgust and disbelief at some of the tweets aimed at Caroline Criado-Perez, and also read some of the commentary, I wonder if there is one aspect of this that has not been considered.
In many cases, I do not think that the intended audience for such trolls is the individual they target. She is just an excuse. What they are doing, it seems to me, is showing off. They want their mates, and the twitter world in general, to see them as big, bad, brave lads.
The target of their abuse will feel it extremely personally, but I suspect that dimension is opaque to the trolls. They may be so self-absorbed that they simply do not consider the impact of their behaviour.