Kill Me Again (1989) on Netflix

The psychopath Vince Miller and his girlfriend Fay Forrester kills a mobster and rob his wallet with a large amount. Then Fay double-crosses the abusive Vince and flees with the money to Reno. She hires the needy private investigator Jack Andrews, who grieves the death of his wife and owes ten thousand-dollars to loan sharks, to simulate her death telling that she wants to start a new life without her boyfriend. He accepts the offer and produces her fake death. However she betrays Andrews and escapes to Las Vegas without paying the rest of the money, leaving him as the prime suspect of her death for the police. Andrews finds Fay in Las Vegas and they have a love affair. Meanwhile the police, the mobsters and Vince hunt them down.