Ouellet-Morin, I., Odgers, C. L., Danese, A., Bowes, L., Shakoor, S., Papadopoulos, A. S., . . . Arsenault, L. (2011). Blunted cortisol responses to stress signal social and behavioral problems among maltreated/bullied 12-year-old children. Biological Psychiatry, 70(11), 1016-1023. doi:http://dx.doi.org/10.1016/j.biopsych.2011.06.017
My doctoral supervisee Jolanta Burke (at Trinity College Dublin) is a positive psychologist, who is currently looking at aspects like this in relation to bullying and cyber-bullying. She may be able to help you. Her website is at http://www.jolantaburke.com. The site is down for maintenance just now, but there is an e-mail contact address there.