Then of course you try calling and she does not pick up. The more she ignores your calls the more upset you find yourself getting. As the feeling of rejection creeps in your actions become more desperate.
This of course leads to a vicious circle of making one mistake after another. So your first vital step is to step back and do not try and call your ex the day you break up. Easy for everyone else to say, I know, but when your emotions are fired up you can do some silly things which leads to more pain.
Step number two is to talk things over with friends, especially mutual friends, as they may be able to give you some good advice. In the case of mutual friends they may be able to talk to your ex to see what is going on. In this step your gathering information and you're not hounding your ex, with this information you can discover what is at the root of the problem.
Now for step number three. Based on the fact that you are acting more responsibly in trying to figure out where things went wrong, the clock is ticking giving you more time to get your head on straight, continue with your life and make the right decisions moving forward.
In this there is maturity, you want to do what's best. Because you have not called your ex she will get the true impression that you are figuring things out, and there is always the fear that she may lose you because you decide that it is not worth getting back together.
The breaking up of the relationship can become a test to see who is committed and who is not. If one partner feels they are going to lose the other then the whole situation can change.
Last but not least once you have gathered your thoughts it is now time to contact your ex. Give her a call and when you start to talk, discuss general topics, do not discuss the relationship, then say that you have to go and maybe suggest a coffee or let her make the move to meet again. Then when you do you can go into more detail, however the key is to make the situation comfortable so that she can say what is on he mind.