I think, people, who can best answer your questions, are the ones who were sexually abused by their therapists.

My abuse was not sexual. It could be best described as emotional seduction, which turns a relationship into a somewhat sexualized "friendship" when intense emotions and mutual sharing are involved and yet it doesn't cross the line of the physical boundary, which allows people to keep pretending that nothing wrong is happening. With this type of abuse I wouldn't say there was a "grooming", not in my experience. To me it was like the therapist simply wasn't aware of his professional role and what it entailed and allowed himself a lot of inappropriate behaviors while still believing he was doing "therapy". And I was too vulnerable and too confused for a long time to understand what was taking place for what it was. For me, like for many other victims, whether they were abused sexually or in other ways, what was happening seemed like something very "special" and, as ridiculous as it may sound, "healing". When you are vulnerable, as clients are, especially those who had a traumatic history, and when you are strongly attached to and dependent on your therapist, you are not in a position to exercise a good judgment. So, people can't really just "stop" seeing an abusive therapist even when they know that he or she goes outside of the lines of the professional conduct. They are way too dependent just to cut the connection and, just like people in all abusive relationships, they stay in denial of what is really happening for a very long time. They keep excusing, rationalizing and justifying the therapist's behavior until they hit rock bottom.

Anyway, that's just my experience..There is a whole variety out there. There are no two identical stories..Each one is unique and yet through most of them you can observe some common themes..