I Want My Power Back

A relationship I was in ended. We didn’t talk for about year. Finally we met and it was a great interaction. I didn’t think we would keep in touch moving forward but I wanted to. A few days little I received a birthday e-mail. For the next 6 months we e-mailed each other to keep in touch. Than it stopped. I sent 3 e-mails that went unanswered so I stopped e-mailing. Recently I started working in the same industry as this person. I don’t want to attend industry events because I know we’ll run into each other. I’m uncomfortable just thinking about what might happen if we run into each other. This person doesn’t want me in their life and that hurts . How do I deal with the hurt feelings over this?