Starting to talk with your ex is a never good idea, especially when you were never entirely confident about your breakup in the first place.
My ex started talking to me again, and there I found myself going online more often than needed and with more enthusiasm doused with inappropriateness. And this is dangerous. Because my feelings are being rekindled, and I am sure they are not being returned.
If you break up with someone, then I believe that no matter how much you might argue, you did it for a reason. The guy can be the sweetest or the greatest, but there is that one thing that came between the two of you. This should never be forgotten, because darling, the first time might be excusable as an honest mistake, but the same mistake is by choice.