PLEASE HELP ME!

by Rahul
(delhi)

I love a girl very much. She loved a boy very much. when i told her my true feelings for her, she thought over it and she agreed.

After few days she herself told that she has started loving me. Her ex boyfriend had cheated her but when our relationship was going on , the ex person suddenly came and asked her for forgiveness and now she has again started developing feeligs for that person and i know that that person is really wrong bcoz i have heard of him through sources.

The girl also knows that he is wrong but then also she loves him. so now please tell me what should i do to tell her that she is doing wrong by having feeligs for that person as the person does not love her?