Every griever has the experience when they lose a loved one or even a less than loved one that their brain automatically starts reviewing the relationship.  We spend time looking at everything we wish we would've done different, better or more.  The griever automatically identifies the feeling the are having as guilt for all the things left unsaid and the the things left undone.  It's not guilt, but regret the griever is left with and this can add another layer to the grief and the pain in our hearts.

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