What is a good coping mechanism when you can’t stop thinking and you have anxiety and depression?

There are many big changes coming my way. But I always overthink everything and can’t stop my mind is always running. I am suffering from panic attacks and the stress is getting way too much. Issues with my living situation, family, financially, physically, mentally, having to go live by myself I don’t want to fall into a bad depressive state because I am alone and then my mind can go to a dark place and I won’t have anyone around to help me.
Asked by PG730

As rational human beings, we often approach anxiety, fear, panic and worry, with the "just stop it" mentality.  Anxiety, although highly uncomfortable and distressing, It can also provide us with valuable information about ourselves and our assumptive worldview.  It helps our brain indicate that "this is important".  The importance may relate to your values, beliefs, and the general quality of your life.   It is okay to feel if uncertain about the experience of anxiety.  Good things can cause and create stress and anxiety, the same as negative experiences.  Our brains can't predict the future, but that rarely stops us from trying.  There have recently been some research studies that anxiety can become a habit-forming experience for our brains.  The study proposes that anxiety, which comes largely from things outside of our individual control, the brain in an attempt to make sense of things, decide I may not be able to do anything about this situation but I can worry about it, and that helps to satisfy something for which you can control.   You are in a similar process, you are trying to make sense of situations that are "new and different".  Overthinking can come from a desire to prepare ahead for any outcome.  I am sure it can maybe very exhausting at times for you.   The goal isn't to think about the future.  Using goals and plans is a very helpful and healthy practice for giving direction and purpose.   What largely drives anxiety, is the thought surrounding the worry.  I would ask you to consider exploring 3 (three) questions regarding your thoughts (if identifiable) around the anxiety  as 1.) Is it true (meaning are these thoughts true all of the time, or are there variables).  2) Is is Kind. (would you say these thoughts out loud to a friend, coworker, or fond family member), and 3) Do these thoughts give me the power for action.  These questions can give you the opportunity to reflect on the source of anxiety and also it may give your brain time to pause and process the contributor to anxiety reducing reaction and increasing production.   I hope you find this answer helpful.  Best endeavors.