ehy dear @leaky20, you were very brave to tell this story, how do you think you failed with sam and how instead of this experience you could improve your preparation as a future therapist.
now I would like to tell you this: I studied pedagogy and a part of psychology. I think a good deal of what you talked about refers to transactional analysis. I also studied communication, that is how the language and words we use are so fundamental to the way in which they are perceived by our interlocutor that often, as you well say, he uses them mainly to confirm wrong perceptions about himself. but despite the knowledge of all these things and the possible tools to make a good analysis of myself, I was not able to avoid the black hole of depression. sometimes the darkness envelops me so strongly that I miss the air. nothing makes sense (even if rationally I don't need a sense, I don't believe in a future life, I think the only thing to do is to live the moment), my uselessness is total. and I feel even worse because I cling to all my knowledge about psychology and despite this I don't find solutions to my suffering.
so you are brave to do your job and try to help those who are hurting because this is a horrible thing and anyone who tries it is blessed!