What I find really interesting is people who are found to have resilience. I don't know much about it but I believe that it's thought that a variety of genetic and environmental factors can account for these differences. It's still a bit of a mystery I think. How some people can experience very difficult experiences say in childhood and come out of it relatively unscaved, whilst others will be deeply affected, why is that?
This one talks about positive emotions and resilience, well that's pretty self explanatory and not suprising;
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1201429/
This one describes children who have grown up with adversity and still shown a remarkable level of resilience, despite their circumstances;
https://en.wikipedia.org/wiki/Psychological_resilience
The cognitive resilience literature has historically focused on specific contexts in which some individuals succumb to stress while others are better able to withstand or overcome it. For example, some children are able to overcome negative life circumstances (e.g., poverty, poor health, violence, lack of family support) that can be devastating to other children These and related studies of resilience have informed our understanding of individual vulnerability to mental health problems such as depression, post-traumatic stress disorder (PTSD), and the onset of schizophrenia Resilience may also help to explain patterns of cognitive decline associated with normal aging and other degenerative processes
There is also an extensive body of research devoted to the study of human performance under stress. Studies in this area reveal and emphasize primarily negative effects of stress on cognition. Unfortunately, beyond addressing training and experience levels, the human performance literature generally fails to address individual differences that may explain or promote resilience to stress.
(I apologise I lost the original source for this).