Just Google 'passive-aggressive behaviour' and 'abuse'. You'll be surprised.
I remember this 70+ couple of pensioners living in a nursing home when i was a student. The wife never once raised her voice, all she did is to complain and guilt trip the husband.
The medical team had to separate them. He had a heart attack and upon investigation it appeared he couldn't even sleep with what's been going on and was really suffering from her passive-aggressive behaviour.
I went ahead and read up on this. Most sites looked something like this one: Passive Aggressive Behavior
This has nothing to do with the 3 comments made by Tara, and the definition of passive-aggression used in this thread.
I did not find any sites that discussed passive aggressive behavior and abuse, and explored real life cases. Reading up, I believe you might be speaking more of covert aggression and manipulative personalities, which is not the same as passive aggressive comments.