Do you think he should leave me?

You could say I cheated on my bf with my ex at the start of my relationship. We never physically did anything or talked about doing anything. But joked around a little and it could look like flirting. Its been several months of me not even talking to my ex and bf brings it up every chance he gets. I know what I did wasn't fair to him. But he forgives and talks to his ex's who have physically cheated on him. And I don't think its fair he forgave them so easy but will probably never forgive me.