Not being able to forget an ex will shut down your mental peace. You are going to be living in the past and not giving yourself a chance to have a good future. It is important to understand that the relationship is over and its time for you to move on.
2) Injustice to Yourself
If you've had a bitter break up or a painful one, your chances of getting into another relationship get scarce. You will be apprehensive of meeting new people and getting into another relationship. Life is full of highs and lows and you need to deal with a break up as a low phase and be ready to give yourself a chance to experience highs again.{relatedarticles}