You've been to a therapist for anger management? Coulda fooled me.
I have read part of Peterson's book back when I thought there was something to him but I have since set it down where it's now collecting dust. I'm on a Robert Sapolsky trip at the moment and I might get back to Peterson if he lets go of his schtick. His best materials are his online lectures, particularly on personality theory (the big 5). He started off strong in his second Joe Rogan interview but his credibility fizzled when he spoke about the root cause of PTSD. He claimed PTSD was an inability for the psyche to mend the horrors a person has had to do in war with their sense of self and self-identity. Joe Rogan then responded (and I'm paraphrasing all this) "I thought PTSD was caused by constant tension from traumatic events or repeated traumatic events and when the feeling of being on edge from not knowing when the next episode will happen becomes pathological.". Joe Rogan was right and Peterson, a supposed Psychology academic, gave a definition of PTSD not used by any credible clinical psychologist.
If Jordan Peterson has helped you with your anger management by inspiring you to make your bed and to speak the language of lobsters, then good for you. But his methods are not conventional nor are they apt for the majority of those who need help, such as OP. He's also gone on a career tangent by being more engaged in socio-cultural and socio-political discourse that speaks favourably to right-wing idealists. So because many see him as a spokesperson of their beliefs and because he has 3 letter acronyms following his name and he's a bit of a media whore (effect of media source credibility), they make an assumption that he speaks the truth. The guy is a hack who plays to the sentiments of the "socially isolated and misunderstood" types who typically reject social norms and deprived of ontological security. But just because you feel like someone wraps you in a safe blanket by confirming your irrational beliefs, it doesn't make him or her right.
Food for thought.