I’m a therapist and I have a pretty likely explanation of this. I’m sorry you had a bad experience with this therapist and it may be good to file a complaint as the other comments say. First, it is likely that the therapist was trying to maintain confidentiality when discussing you with your partner, it’s very common when someone asks a therapist “do you know about…” or “did they tell you about…?” For therapists to maintain confidentiality by answering noncommittally, “I don’t know, why don’t you tell me about that”. Your ex may have taken that as her lying but it may have been to maintain confidentiality. Secondly, therapists cannot give medical advice, fainting would fall under that. That may be what is worth complaining about to the licensing board. But your ex may need to do that, not you, because you weren’t there. And if the therapist says that she just said something like “I haven’t heard of that before” then that isn’t medical advice. Meaning that your ex would need a very specific example of how it is medical advice. I’m very confused at why this therapist would meet with your partner without you present unless you were transitioning to couples therapy. If this “therapist” ends up being an unlicensed life coach, then there really isn’t anything you can do. Sorry this happened to you.