Hi Marce,
In my experience and from what I have read about relationships is that they end around the one year mark. This is when the romantic phase ends and the power struggle phase starts. http://www.loveatfirstfight.com/relationship-advice/relationship-stages/.
Both parties play a part in the success or breakup of the relationship. You can beat yourself up or when calmer, you can learn from the relationship. You ex has responsibility for his part. If that fact helps you deal with blame then I suggest you examine how your ex’s behavior helped caused the demise.
Plus acceptance of the end of a relationship is part of the mourning process. It may help to realize that there are stages to that as well.
I wish you peace Marce and patience with yourself.
Mark