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The reason why so many couples break up and get back together is because their emotions can quickly spiral out of control and often the words "it's over" fly out of their mouth. Regardless of the reasons your ex gave you for breaking up the fact is that you need to accept that you might not have been told the entire truth.
The most important thing you understand right now is that there is a very big chance that your ex maybe having or may have serious second thoughts. With this in mind you must avoid making stupid mistakes that can reaffirm the decision they made to leave was the correct one! This is where so many ex's go wrong and destroy all hope of reuniting with their partner.
The very last thing you want to do right now is make your ex feel that breaking up was the answer! Make sure you keep your emotions in check and under control at all times. Don't let your heart break and pain to take over you and make you do and say things that you may quickly regret. Don't become your own worst enemy during this time.
Breaking up is rarely final if you understand how to approach this next stage. I understand the pain you are going through and the paranoid thoughts you must be having worrying about if your ex stil loves you or will her or she meet someone else soon. The fact is that love is rarely the reason for a break up or break down in a relationship.
There is a great chance that your ex still loves you but they can not continue another day on the path your relationship was on, with that in mind it should tell you that things can be turned around and you can get back together after a break up if you play your cards right.
There are some terrific step by step guides you can find on this site that will take you by the hand and teach you exactly how you can turn things around and get back together.