Teens: What should I do?

If she loves you, she shouldn't hold you back from what you want to do. She should support you, because those are chances of a lifetime. BUT, I do see where she would feel lonely. Just sit down and talk to her about what you want. Find out if she could handle going to different schools. And if not can you handle losing her and focus on college? I would go with going to Duke, but I would also talk to her as soon as possible and finding out her opinions. And like I said, if she loves you, she should support you.