The hard-partying late son of accused murderer Alex Murdaugh allegedly beat and strangled his ex-girlfriend — and once had his family cover up his drunken driving crash, the former flame claimed.

Morgan Doughty, 23, who dated Paul Murdaugh in high school, spoke out for the first time about the harrowing abuse she allegedly suffered at the hands of the youngest Murdaugh in the Netflix documentary, “Murdaugh Murders: A Southern Scandal.”