Annette Creegan was formally identified by Norfolk Police after her body was found in the River Bure on the Norfolk Broads on Sunday.
Detectives believe she was dead before entering the water, probably as the result of strangulation.
Her partner, named locally as John Didier, died as the result of drowning. His death is not thought to be suspicious.
Police launched a search for the bodies after finding a 13-year-old girl alone on a boat after a hire company alerted police that the vessel had not been returned on time.
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