Step1
Make a decision. Ask yourself: do you want your ex back, or not? If not,
then DECIDE that you are going to get over your ex. Right now.
Getting over your ex is a task, no different in principle to achieving any other task, like learning to ride a bicycle or drive a car. And all tasks begin with a decision.
Most people never reach their full potential in life - sadly, many don't even come close. In most cases, they simply didn't achieve what they wanted because they never made a conscious decision to do so.
It sounds simple, and that's because it is. Many people would like to be rich, yet never actually decide that they're going to be rich. Anybody can get lucky and win the lotto - but why leave things to chance?
Step2
Once you have made your decision, formulate a plan. Simply ask yourself: what do I need to do to get over my ex? Ask yourself over and over until the answers come to you - and they will. You already have everything you need inside you, you just have to access it.
Perhaps you'll decide on taking a short break. Maybe you'll get a part-time job or enroll in a new course. You could take up a hobby, join a club, get involved in a group, go traveling etc. All the above create the potential for meeting new people and having new experiences.
On the other hand, sitting at home thinking about your ex does not create new opportunities for you.
Step3
Stick to your decision. Every time you catch yourself feeling 'the old way' about your ex, REFUSE to be a slave to your feelings. Tell yourself: I will not carry on feeling like this. It stops here and now.
Realize that you are an adult, and that YOU are responsible for your own thoughts - NOBODY is making you think anything! It is YOU that's playing scenes from the past over and over again. If these scenes aren't helping you, then stop playing them!
Enthusiast 
