While the normal methods for rekindling a relationship with your ex may not be successful in the case of infidelity, there are other methods that will. Your ex not only feels betrayed and hurt but she feels insecure about herself and her position as well. This situation doesn’t have to mean the end of the road. In some ways it can be easier to regain your relationship after an affair than if your breakup happened for another reason – her feelings for you never changed. She’s just too upset to recognize that they’re still there in the heat of the moment.
It's important to not just talk, but to listen and hear what your partner has to say about what's going on in your relationship. You can show you're listening by summarizing what your partner has to say to show you've understood what he or she has said. You can also ask questions that show you've heard what the person has said and that you want to know more.