If your ex asked if you are dating then, tell him yes because my last experience was bad, and I am still searching, it will be a sarcastic answer because he was your last boyfriend, or he might have asked you because he wants to know about your relationship status that you found someone or not, there can be two reasons 1st if he is still hung up on you that's why he must be asking and 2nd he just wants to know what's going on in your life, but if your ex asks you to get back together, the girl remembers why you broke up never get back together with your ex.