I have problem can someone help me?

Shame on your "ex" for asking you to meet him for lunch. He knows that you are married and have a little girl. Yes, you are allowed to have a "guy" friend, but you are playing with fire if you are meeting him alone. Call it what it is: you are rebuilding a romatic relationship. Make time to "just talk" with your husband instead. Communication is what keeps a marriage, or any other relationship, alive.