It isn't dumb that you still have feelings for her. You were together for two years, so you are experiencing a sense of loss. In addition, given the circumstances of your breakup, you are probably feeling betrayed and confused. All of this is normal.
To answer your question of how to get over her, the only answer to that is time. During the time it takes you to get over her, distract yourself. Stop using the forums that she does. Stop looking at her facebook page. Cut off any opportunity for you to see what she has going on and concentrate on yourself. Do things that interest you. Meet new people. Don't let her keep you from living your life.
Good luck.
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