I have met three INFJ females in my life, one of them I dated and all of them I would lable as mentally insane. Mood swings?! More like self-destructive rampages that immediatley switch to ear bleeding crys of apology. I do not get it at all. This could just be a coincidence but I dont know, I highly doubt it beings they all 3 (none if which knew each other) had very similiar "tantrums".
And the one INFJ male ive met (BMS) is truly a character but I wouldnt lable him insane like I do them. So I wonder if its just a gender thing or if they really where crazy.