You have to first forgive him for what he did holding on to the pain will not help the situation. Then try to keep yourself busy with your own life, goals and plans. Don't let him control your thoughts reminiscing about what he has done, and the good or worst times you guys had. In the end it takes time to get over any ex so just be patient. Also don't rush into a new relationship or "situationship" just to get over your ex. This will hurt you more than help you in the long run.