Dating Don'ts: Stay away from the topic of your ex. No one wants to hear that.
If something reminds you of your ex-partner, especially when you're beginning another relationship or dating--that's completely normal. But this is one of those things that you just have to keep to yourself for a little while. If someone is still getting an impression of who you are, they wouldn't be happy to know that you're thinking about your ex on your first date.
But is there a magic time period that goes by where it's okay to have the 'ex talk'? Expert matchmaker Emily Holmes Hahn says--absolutely! She said it's OK to bring it up on the third date if the mood is right. That seems early, but it's important for your partner to understand that you, too, are vulnerable, and that they don't have any reason to feel jealous or insecure about your history.