Personal experiences, including traumas occurring prior to joining the forces, can have an impact on whether or not someone will develop PTSD after an incident.
I can't speak for your province, but in Ontario we have a shortage in general of medical doctors, specialists, and even psychologists, and in fact in order to see a psychiatrist or one of these practitioners or in order to have your insurance company—if you're lucky enough to have insurance—cover it, you need to have a referral from a family physician.
Could part of the problem be, at least in the background, the fact that the basic medical services just aren't available in some provinces?