Exactly this. I now think that my first therapist had experience with NPD and was treating it without me realizing that. But then I felt the progress was too slow so changed the therapist to someone who I now think did more damage than good. During this time is also when I had my collapse. Due to fortunate circumstances I’m now finally going to a therapist who is extremely experienced with NPD and does not let me fool her or myself. So to your point, yes it’s very tricky, and @zwkrt comment above is very accurate.