A 52-year-old widow is referred to psychiatry by her primary care physician for evaluation of depressive symptoms following the death of her spouse 4 months ago. She reports persistent sadness, guilt about surviving, difficulty sleeping, and weight loss of 8 kg. She denies suicidal ideation but admits to passive wishes that she could 'join her husband.' On further questioning, she reveals she lives alone, has limited social support, is retired with modest fixed income, and her only son lives abroad. She has a past medical history of hypertension managed with medications. Mental status examination shows psychomotor retardation and restricted affect. Which of the following clinical features is the MOST SIGNIFICANT indicator of elevated suicide risk in this patient?