Everyone experiences those intense emotional reactions when stimulated by an upsetting event, including unwanted changes in a person’s life. It’s natural for all people to dwell on the emotional event, especially a significant one like when a parent or pet passes away. People with ADD are more likely to have these deficits when it comes to emotional regulation, which is the ability to modify an emotional state so as to promote adaptive, goal-oriented behaviors.
The Anterior Cingulate Gyrus is the portion of the brain responsible for allowing us to move from thought to thought, co-operate, and see errors. It is basically a shift-gear that transitions our attentions away from emotional events. An overactive anterior cingulate gyrus may will cause a person to get thoughts stuck in their head, worry excessively, upset easily, and obsess over things. The cause of an over-active anterior cingulate gyrus is low serotonin levels in the brain.
I’d don’t know your situation, but I’d imagine it’s tough watching other people get on with their lives. I’d advise you to look for other positive distractions in life.