Here are links to 9 articles, from PC's archives, that (hopefully) may be of some help:

When Ruminating Becomes a Problem

Why Ruminating is Unhealthy and How to Stop

8 Tips to Help Stop Ruminating

5 Mindful Treatments for Rumination

Catastrophic Thinking: When Your Mind Clings to Worst-Case Scenarios

https://psychcentral.com/blog/naviga...dium=popular17

https://psychcentral.com/blog/naviga...inking-part-3/

https://blogs.psychcentral.com/weigh...from-yourself/

https://psychcentral.com/blog/when-y...like-yourself/

My best wishes to you...