What do i do when a girl I've been talking to tells me she might still be in love with her ex?

The situation is I've been talking to a girl that's recently broken up with her Ex of 9 months during the summer. He cheated on her and she was deeply hurt. I've only spoken to her for about 3 weeks and shes said that I'm like the only person who really has her figured out the first week we spoke. I suppose that I'm helping her through it. One night while we were talking she asks me if I've ever been in love. I told her "No, infatuated maybe but not love." and i asked her if she loved her ex. She says yes and that she still might be. I really like her and she's worth every bit of the trouble, but I don't know what I'm suppose to do, do i give her time? or do i let her know that I'm there for her? Help is greatly appreciated. Oh and we're both at the age of 16 if that helps.