The first few days after a breakup are marked with pain and a whole lot more unfocused anger. First comes the night of when your friends pull your trashed body out of the bar and onto the sofa with a trashcan next to your head. Then comes the next few days of anger and trash talking when you become convinced they must be incredibly stupid to have even thought of letting you go. Last, comes the acceptance and reality check, when you simply wonder what the hell really went wrong in the relationship? Understanding why you were left or dumped is one of the most important parts of moving on with your life and building a better relationship in the future. Surprisingly enough, it actually could have been your fault. Look over the next few common causes of being left behind and evaluate yourself to see if you could have fallen victim to committing these cardinal relationship sins.