Mindfulness.

Google “John Kabat Zinn Body Scan” and use a few times a day whenever triggered.

Use that as a platform initially, and then do more reading into mindfulness training.

It’s essentially being able to step out of your own head and look inside from the first person. It can be a window into developing awareness of your bad thought patterns, cycles and triggers.

Google “stop sign imagery”. Can be a super useful technique for the short term.

And physical exercise. The answer to “I feel triggered, hurt, upset, overwhelmed” - should always be “I’m going for a 30 min run.”

It breaks the rumination, overthinking, stress cycle.

Good luck!