Before the words of another can have the power to crush us , some part of us must identify with and believe that the words are true (at least partially).
Why does one person laugh off teasing, not giving it a second thought, and another become highly offended and perhaps hold a grudge for life? In both cases, the words are the same. Why do they have power in one situation, and not another? Because the hearer gives them power according to the meaings they attribute to them. Someone who has general low-self esteem is more vulnerable to the words and meanings of others. Or, an individual could be sensitive and vulnerable in just one area. They may shrug off the snipes of others nonchalantly, until one is aimed at the "sore spot", then it becomes a fatal blow.
It is helpful to remember that words are just words, they are not "truth" in themselves. They may be the speaker's current perception of truth. So, they truly do say more about the speaker, than they say about us (an oft repeated maxim). Our reaction or response to the words is more telling of our own issues. When we feel such a powerful reaction to others' words and opinions, it is good to ask ourselves, "What identity or persona of mine, (aspect of self) feels threatened, by these words. What attachment do I have to this ego identity? How did it arise? Can I let it go?
These types of questions can give us valuable insight into the inner workings of our minds and how we generate meanings and attachments.