Did the therapist claim to be accredited?
Did your friend pay the therapist and how much?
If the therapist misled your friend by misrepresenting what she was then your friend has grounds to sue for some or all of the money paid.
The police are unlikely to take action even though the actions of the therapist could be viewed as fraudulent if she misled your friend about her qualifications and ability to help.
The therapist would not be in public office in that sense. If she was a member of a professional body she could be struck off the register of that body.
She needs to have committed a criminal offence in this case. The fact she did in others such as assault does not make her guilty here.
The most likely offence here would be fraud since she took money on false pretences.
Yes I am saying that fraud is the most likely charge provided the police feel they have enough evidence in your friend's case.
A public officer is one who holds a public office such as Mayor, councillor , MP etc.