'It does seem to me that entire communities do become mentally ill, however.' - please provide evidence supporting this statement.
I'm not sure how change will come about. I have read about acts of kindness from moderate sunnis in the Syria/Iraq conflict. Some kind people helped escaped yazidi slaves by hiding them away from ISIS, helping them reach their relatives in Kurdistan or Turkey.
Some activists in Ar-Raqqa are documenting human rights abuses but I'd imagine their life expectancy is about the same as an icecube in an oven.