I think it's something that's probably not a conscious decision for most. Everyone responds to any negative stimulus by engaging coping mechanisms. While we can argue til he cows come home about good and bad strategies, the brain generally doesn't, it just grabs the nearest and, if it helps alleviate the effects of the stimulus, it gets the gig.
The sad fact of the matter is that both avenues (becoming a better person and becoming a dick) can lead to a perceived alleviation. It's a crapshoot. Good support would make all the difference but, in the absence of good support, luck, intelligence and a strong sense of self awareness are probably the main deciders.