Thanks for raising this issue. I have great difficulty with this....have made a big mess of many areas of skin...and the urge is so powerful I sometimes cannot resist. Years of physical and emotional abuse as a child and domineering parents (I still feel dominated even though they are quite old) are the reason for this. It is very hard for me to express anger and I am internalizing all these feelings.
I read somewhere that could not imagine hurting anyone else like this, or standing by and watch someone do this to themselves without being horrified. Yet the behaviour persists....I have also read that dopamine is somehow involved...can anyone shed light on this problem?