Wow, that is absolutely disgusting in so many ways that you're being treated like that, I'm so sorry.
You have your rights, and one of those is to choose whoever you want to see - a GP included. You have the right to be treated with respect in all aspects and taken seriously. They're pretty basic rights but they should be acknowledged by health professionals and they should treat you kindly and help you, even if you're just getting a prescription.
I'm so sorry that the whole clinic is treating you horribly. If it makes you feel any better, I also live in a small regional town (4,000 or so people here). There's only the 1 clinic in the actual town. So I know how hard it is to find a good GP & health professionals who deal with mental health, trust me.
My advice would be contact the HCC (Health Complaints Commissioner), or even the MHCC (Mental Health Complaints Commissioner), look on their website for how to make a complaint & do it. Because how you're being treated is just wrong in so many ways, you don't deserve any of it, and I'm sorry you're unfortunately dealing with such rude unprofessional people.
I hope you find a GP that you feel comfortable with, who treats you with respect, who you can trust, & who does their job correctly, including prescribing you meds. & someone that actually has knowledge, especially of anything mental health.
Again I'm so sorry you're dealing with this. I know how you feel because my GP is horrible too & they make me feel bad for changing GPs there. I don't know why. Even the receptionists are rude & unhelpful there.
I really hope things get better for you, & I hope you can find the courage to make a complaint because this should not happen to you let alone continue to happen, & it shouldn't happen to anybody. It definitely needs to be addressed & complained about in my opinion because none of it is acceptable in any way.
Love & hugs, I hope things improve & you find a GP who is good for you in all the ways you'd like.