Gwen Costello was Frank Costello's wife. She is not affected by violence in the slightest as Frank had a severed hand at the table and she did not even acknowledge it. She truly does love Costello and is not in the relationship for his money (although it probably didnt discourage her from perusing a relationship) because she is seen in their apartment reading 'Getting Pregnant'. Her reaction to Franks death is never seen.
She was portrayed by Kristen Dalton.