Final answer:
The provided reference material does not contain information about the death of Henry Wadsworth Longfellow's first wife, Mary.
Step-by-step explanation:
Henry Wadsworth Longfellow's first wife, Mary, did not die in the provided reference material as it does not pertain to Longfellow.
The text provided covers the life and works of Mary E. Wilkins Freeman and other unrelated historical figures. For accurate information regarding the death of Longfellow's wife, one would need to consult a reliable source that details Longfellow's personal life and biography.