On an inpatient unit, a 31-year-old single woman reports experiencing auditory and visual hallucinations for 1 month, followed by a full major depressive episode for 2 months. The psychotic symptoms and depressive symptoms occurred concurrently for 3 months, until the depressive symptoms resolved with pharmacotherapy and psychotherapy. The psychotic symptoms persisted for 2 more weeks, at which time the patient checked herself into the hospital. Which diagnosis best fits this clinical picture?