A 58-year-old male presents for psychiatric evaluation seven months after the death of his wife from pancreatic cancer. He reports persistent sadness, tearfulness when reminded of his wife, difficulty sleeping in their shared bedroom, and reduced interest in social activities he previously enjoyed with her. He states that he sometimes hears his wife calling his name when falling asleep and occasionally sets a place for her at dinner before catching himself. He reports that he can experience moments of positive emotion when spending time with his grandchildren and finds meaning in volunteering at the hospice where his wife was cared for. His appetite has been reduced but stable, he has lost six pounds, and he denies suicidal ideation, worthlessness, or guilt beyond regret about 'not spending enough time together.' His PHQ-9 score is 14. Which assessment finding pattern most reliably distinguishes normal grief from a major depressive episode in this patient?