i think showing vulnerability as changeling suggest, is an invitation for someone to take advantage of, or attack you. it is like the animal kingdom, some animals avoid a fight all together by flexing. i think if you are perceived as someone not to be f*@ked with, your less likely to be a victim. that doesn't mean act like a hard ass all the time, but, just letting people know what you are capable of is sometimes enough.
for instance, i am a big guy, and when i go to bars, i meet 2 types of people on average. either people try to be extra nice to me, or, people want to challenge me. now, i love to fight, but, try to avoid it as much as possible. i hate all the drama that comes with it. one night, i was at a bar, and this guy would not leave me alone. i was on a date, and really didn't want to get into it. well, he saw he couldn't get to me, so, he started picking on my date. that was it. i was smoking a cigar. i looked at him, put the cigar out in the palm of my hand without flinching, looking him in the eye. i calmly said, you ready to go outside? he walked away. okay, now i'm rambling, but, hopefully, you see my point.