Perhaps you could talk with the practice manager at the surgery. I work closely with GP’s and often they would refer people to substance misuse services to manage not only the pharmacological side of things but also the psychological. Sounds as though you’re now in the right place/direction.
Remember you are not responsible for how someone treats you (that’s their behaviour) you are only responsible for your reaction to the situation. Could be she/he was having an “off day” – we all have them right? No one’s perfect. Could be she/he was directive in an approach – doctors can come across and clinical and work with outcomes etc so might have lacked empathy. When you’re going in there talking about personal stuff and being brave you probably expected some support. Or she/he was just poor practice – who knows. But, perhaps move on now, share the experience and focus on you.
Well done though for getting the support you need. Not an easy journey to go through and defo not cold turkey! All the other stuff is noise that will affect your recovery.
Good luck to you