Ex-boyfriend fell in the hands of a friend

Maybe it’s that I feel now. I do not know how to behave. This talk about matters of the heart. Not an easy thing to be forgotten. Do I have to impose my feelings have fallen in love with him? Maybe it’s a wise answer. But to do so is not easy. Conversely, if I impose this relationship, how should I behave to my friend?
Sometimes I feel the turmoil heart awry. About this relationship. Can anyone help me, please? : ‘(