Most of your post is hard to follow, but a highly-cited fMRI study found that
In summary, a pattern of activations very similar to those found in studies of physical pain emerged during social exclusion, providing evidence that the experience and regulation of social and physical pain share a common neuroanatomical basis.
Likewise a newer study concludes that:
rejection and physical pain are similar not only in that they are both distressing—they share a common somatosensory representation as well.
An even more recent study has challenged these though:
Pain- and rejection-related representations are uncorrelated within regions thought to encode pain affect (for example, dorsal anterior cingulate) and show distinct functional connectivity with other regions in a separate resting-state data set (N=91). These findings demonstrate that separate representations underlie pain and rejection despite common fMRI activity at the gross anatomical level. Rather than co-opting pain circuitry, rejection involves distinct affective representations in humans.
Since most of the "hurtful" words on SE are of the kind that lead the receiver to experience some level of exclusion (not being "good enough" to be part of the site[s] etc.)... it seemed appropriate to mention this. Of course you can make someone feel excluded while being perfectly polite.