"Could I have done more?" that's a question a Holland woman asked on Monday after she witnessed the murder of her best friend earlier this month.

Elizabeth Popma says she was sitting right next to Crystal Latham when Latham's boyfriend Keith Williams stabbed her to death in Holland on October 9.

"You play that would of, could of, should of, stuff," Popma told WZZM 13 exclusively on Monday. "I just loved her so much."

Elizabeth Papma thought back to the last moment with her best friend.

"All of the sudden he just charged from the kitchen to us within seconds," she said. "At first he started punching her in the face and I was just like, 'Stop! What are you doing? Stop! Stop!' then I see the knife go up."

"I ran outside and the neighbors that happened to be out there, 'I said dial 911, dial 911! He's killing her! He's killing her!'"

Police and paramedics arrived shortly after, but it was too late. Latham was gone. Now all Popma has are cell phone videos of Crystal, laughing and smiling just days before the murder. As Popma scrolls through them, a wave of regret comes over her, wishing she would have taken action when saw the signs of abuse.

"I seen the strangle marks on her neck, the red hand prints," she said.

"I kept telling her, 'this man is going to kill you. He's going to kill you'. When you feel that you're in trouble in your heart of hearts, get out. Just make sure you get out," she continued as she began to cry.

"There's so many resources available in Holland alone, people are willing to help you got to make that first step, you have to."

Keith Williams is expected be in court later this week for a probable cause conference. He's been charged with open murder which carries a life sentence. During his video arraignment earlier this month he admitted to killing Latham.

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