To some, Nicole ("Nikki") Addimando is a young mother who shot her abusive partner in self-defense when she feared he would take her life. To others, she is a murderer who took the life of Chris Grover, a father and popular gymnastics coach in Poughkeepsie, N.Y. Now, 48 HOURS and correspondent Jericka Duncan investigate their relationship and the night Grover died in "The Case Against Nicole Addimando."