Me and my ex were dating for a few months and we were both getting these feelings towards each other. We nevered argued I got along great with here kid. Then she tells me she's scared of likeing me and broke it off. What can I say or do to get her believe there nothing wrong in in liking me?

Nothing. You give her space. If you are the one for her, she may come to that realization on her own.
You cannot make someone want to be with you or be in a relationship