You might want to check out HeyPeers - Where Peers and Support Groups Connect as they may be able to help or at least guide you to the right resources.

Books involving dialectical behaviour therapy and also schema therapy would be helpful. If you can't get them at your local library (check to see whether they will order a copy for you), then you may want to get a secondhand copy at AbeBooks | Shop for Books, Art & Collectibles.

Also, check out InsightTimer for guided meditations and look up "Jon Kabat-Zinn the mountain meditation".

There is also the 4-7-8 breathing technique which Dr. Andrew Weil and others explain how to do on the net.

Book or audiobook of "Hope and Help for Your Nerves" by Dr. Claire Weekes. (There are YouTube clips, as well.)

And last but not least, the raisin meditation: Raisin Meditation | Practice
| Greater Good in Action

Hope that helps!

All the best in your healing journey