Confused, I Need a Suggestion

So, I started talking to a girl in February and things were going well. She was going through a breakup and appreciated the effort I was putting in. She keeps saying I am her last ray of hope, but she still has feelings for her ex. Her ex has been talking to other girls lately, and now she is asking me for space. I told her I couldn't give her the space she needs, but she said I already agreed to it. I have met her multiple times, and she is always excited whenever I am in the city. I live in other city and visit her city often. As we moved forward, we became intimate and she showed clear feelings for me. She always cries whenever I ask questions like, "Who am I to you?" Suddenly, she is asking if we can just be friends until she moves on. I'm scared that she will go back to her ex again, and he knows everything that has happened between us. I don't know what to do. Can anyone suggest what I should do?