What are some of the stressors that commonly drive people to psychosis?

Not what happens. Psychosis can be an inherited condition or a chemical imbalance in the brain. Stress may bring out the symptomes, but it doesn't cause the disease.
Trigger not cause. I agree with dr. Majerone. Psychosis is loss of touch with reality. It may occur with patients who have schizophrenia, schizoaffective disorder, mania, severe depression, schizophreniform disorder, brief reactive psychosis or certain personality disorders. Medical causes of psychosis can include dementia, drug or alcohol intoxication or withdrawal, brain tumors, medication side effects >>>.