A passive aggressive has the most annoying personality out there, imo. I think people are either passive aggressive or they aren't. It has to do with temperament and how someone deals with conflict and power struggles--in general. A person who cannot comfortably express their needs and frustrations, will resort to PA behaviors. If you want to avoid dealing with this type of person--which you do, btw--steer clear of non-assertive types. I am not a passive aggressive at all. But I can spot one a mile away.
One can be passive (non-assertive) and not be a aggressive, however. A PA is angry and frustrated but unable to resolve these feelings in a mature and healthy way. So they cryptically sabotage situations, belittle others with barbed comments, forget to do things, and exercise willful ignorance. They will literally drive you crazy and never admit that they have acted aggressively and hurtfully. They will say you are imagining things--you are crazy. This person will never change--even with therapy. Best thing to do is keep them at arm's length and out of your inner circle. If you marry someone like this, you can look forward to years of misery and eventually a divorce--initiated by you.
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