I belive I may have found a 1964 marriage records for Mary Lue Kelly.
The husband Albert Bubba Johnson may have been the family member Mary Lue Kelly went to Florida to visit.
Florida Marriage Collection, 1822-1875 and 1927-2001
about Mary Lue Kelly
Name: Mary Lue Kelly
Marriage Date: May 1964
County of Marriage: Duval
Volume: 2220
Certificate: 14604 Source: Florida Department of Health
Florida Marriage Collection, 1822-1875 and 1927-2001
about Albert Bubba Johnson
Name: Albert Bubba Johnson
Marriage Date: May 1964
County of Marriage: Duval
Volume: 2220
Certificate: 14604 Source: Florida Department of Health
This is probably the husbands death record.
And he was born 1937 so the age seem to fit:
Florida Death Index, 1877-1998
about Albert Bubba Johnson
Name: Albert Bubba Johnson
Death Date: 19 Jul 1989
County of Death: Dade
State of Death: Florida
Age at Death: 52
Race: Black
Birth Date: 12 Feb 1937
I have informed the Broward County Crime Stoppers