Many here are in situations similar to yours, not exact, but similar.
The majority here who have quit substances mostly agree that their problems, challenges, anxieties , feelings of worthlessness, powerlessness, depression, etcetera are more easily taken care of not under the influence of something.
They are grateful for their sobriety from whatever they are sober from, and feel like the sobriety is what gives them the power to deal with what they have to deal with.
I’m happy for you that you do have some sobriety time behind you, I’m sorry for the circumstances that made you feel like you needed to start again.
Hopefully you will find it in you to quit once again. There is lots of support here for that.
Overthinking can be brutal. If you are able to talk to a doctor about that it would be helpful. If not, then that’s the answer to that.
Sometimes just talking about what bothers you is very helpful in and of itself. Even if you do not get into the very specifics.
Again, welcome to the community.
There are many topics here that could be helpful for you.
One is the meditation thread where people are listening to meditations, etc. on the Insight Timer app, which is free.
Here is the link to that thread.
When your mind is busy overthinking consider listening to one of these. You can search with in the insight timer app for more specific to your circumstance meditations.