Many people who have Borderline Personality Disorder report that they typically will excessively ruminate over a negative experience they have gone through. The continual revisiting of the event and possible consequences can become obsessive. The difficulty is that they never seem to come to terms with the event and are unable to move on; they feel trapped in the constant recycling of the event and the negative emotions attached to it, such as fear, shame, anxiety, anger, etc. And the more they mull it over, the worse it gets, often leading to the conclusion that they are at fault and less than worthy person.
Resetting the connections between the areas of the brain involved in the process can help stop the recycling nature of the rumination phenomenon. As daunting as that sounds, there are actually some relatively simple activities that can help you step off the rumination treadmill. You can learn more about this in a recent online article published in Psychology Today