The cop is commendable for trying so hard, but he was gong about it the wrong way.

He was invalidating the fuck out of her. Her emotions should have been acknowledged, because they are real and valid. That cop cant tell her how she feels or what she wants. She even called him out on it saying, "you dont know me." which is 100% true. He couldnt even recall that she has two daughters (understandable under the pressure.) Invoking the children is a good tactic, but saying "they don't need this" adds to how she was already feeling.

A better approach would be something like, "that might be true. I know you feel really bad about yourself right now. we all make mistakes and act in ways that we regret. you are right, i dont know you. but I know this will the biggest mistake you'll make. give yourself a chance. make this the day that you stop being a piece of shit. If you cut your life short, you will never show your children that they can rise from hardships and improve themselves."

I know exactly how she feels. I've said those things about myself verbatim. The fact that she held on for so long shows that she was crying for help, at least a little bit. If you are ever in this position, validate the fuck out of the person's feelings. Show them that they aren't invisible. Understand them. Let them know that they are allowed to feel any way that they feel. BUt acting on it is the worst thing that they could do.

The cop still did a great job though. Way better than cops can usually do. Usually they would just shoot the poor people immediately. She even threatened him. At least he tried.