It is very interesting to know that a break up does not mean that it is the end of the road for your relationship. For what it is worth, there are many times when a break up wakes you up and makes you realize the true value and worth of your relationship.
As weird as it may sound, sometimes it makes you an better person and when you get your ex back for good this time, what you will end up having is something sweeter than ever.
Now what you should do if your ex decides to call it quits is give it some time. You want her to think about what she did and you also may want to think about what you want in your life or maybe what are the things that has led to the separation. Truth is, it is not really you that your girlfriend does not want anymore but something in the relationship that has taken its rot.
It can be the way you do not spend enough quality time together or maybe the way you have neglected yourself because you have gotten complacent in your relationship. There are many reasons and it is a good thing to take note of them so that when you do get your ex back, you can have smooth sailing days ahead.
Launching an all out attack the day after she stormed out the door is not a good idea because emotions are still running high and you may be too tensed yourself so it is best to allow room to cool down then call her and invite her to meet on a very casual level. The casual part is important. Do not say anything about the plan to get her back for good. Just ask her out and see the chances that you have. If she says yes, then you know you have solid footing to get your ex back for good.