hello OP. I have a friend who sadly became involved with some very unprofessional therapists, one of whom was abusive and between them they triggered a traumatic reaction which almost caused her to have a further breakdown.
All of them were members of recognised professional organisations.
You can take out a complaint if your therapist was a member of such a body. However, in my friends experience, the whole thing was a nightmare, it took years, the professional bodies seem more concerned with protecting their own members. And if the therapist is insured, as they should be, they will have fancy lawyers on hand to fight you all the way, whereas you may have very limited resources.
You need to think hard about whether you are strong enough to undergo this lengthy process, which can be damaging in itself.
Even if you 'win', the professsional body may just give a slapped wrist and the therapist can more often than not continue causing damage.
On the positive side, after four years of struggle, my friend does feel vindicated as the various tribunals before which she represented herself, did agree with her version of events. She found this quite empowering. But she did have a lot of emotional support and has friends who are very knowledgable in the relevant area.
If you look up the websites for the professional bodies mentioned above, look at their complaints procedures.
To chose a new therapist, maken sure they are qualified and belong to a prof body, you should be able to have an initial free assessment interview, where YOU can see if you feel comfortable with the therapist, and remember to remain in control and end the relationship if you do not feel happy and safe with the process at any stage. Good luck