The single most stressful life event on the life stress scale is the death of a spouse?

NO. Losing a spouse is NOT a "top stressful life event" .... it would be in the "top life traumas"

I respectfully disagree. Death of a spouse IS a life event, and in fact, is #1 on everyone's scale of most stressful life events (it is #1 on life events for adults; death of a parent is #1 for non-adults).

Even things that should be happy occasions (vacation, holidays) have a stress rating.