If it was done by one (toxic or dangerous) person, ask why you should go back to this relationship at all. Learn from it and try not to carry destructive patterns further - but remember where to find red flags next time.
Since trauma can become very destructive (for me it's overeating, snapping and neurosis badly influencing my health), there's psyllocybin and guided therapy to help. Or at least normal therapy helps well (and should go before any meds or drugs), to sort it out and talk it out.
Gabor Mate is very good on trauma, he was at Joe Rogan's. Check it out on Spotify or him on YouTube.