If I want something cleaned up, then I get impatient and starting cleaning it myself, I don't see how that would be malicious or "passively aggressive". That's "I need this place clean, and if you won't do it I will". If I'm really irritated about it, I'll...confront them directly about it. Is that passive-aggressive? If so, how the hell would you clean something up without it being passive-aggressive, if you've already asked someone to clean it and they don't? The only way I can see is for you to wait until they leave, but that isn't always going to happen anytime soon, so...

And how do you tell apart fake sympathy from real sympathy? I used to think it was obvious but I am increasingly unsure. o.O

I'm just not sure what to do with that last one. People tell embarrassing past stories all the time for fun, so I'm not sure how to tell when it's being done out of anger...?