Hi and welcome to beyond blue.
The answer to your question is to be able to find and use distraction and coping tools/techniques to bring you back to the present moment when your mind is stuck on treadmill of worry or negative thoughts. As for resources to help you...
- you could start with the threads on grounding and mindfulness.
- you could also install some mental health apps on your phone such as smiling minds, or relax melodies
- there are also books (there is a thread here on books also) such as "the happiness trap" you could look at.
- and if the above do not work there is also the option of getting professional help.
Of course, it also helps to be able to identify what you triggers are to be able to use the tools.
Hope these ideas help you, and if you want, please come back and we can chat some more if you have any questions or....