Hi everyone

First time posting....kinda shy and not very assertive poster here. Please be gentle.

Yesterday was my first day back to work from short term medical leave. My work /office contributed substantially to my GAD. I have a bunch of really uncompassionate, militant, bullying, and unempathetic managers running the shop. My long term plan is to transfer to another government department but that takes time.
My psychologist is working for my insurance company who's been paying me while I have been off work getting my GAD under control. However, for the most part, my sessions with this doctor have been a waste of time. Any help I received has been through my own and with the passage of time.
Any how, my supervisor manager is a real mean and uncaring person. I had asked my psychologist to make a recommendation to have me transferred to another section or department considering how toxic the work enviornment is and what it was doing to me. I argued that I would be able to placed elsewhere if I had his support but he declined. He said try it out at work and look for another position or job in the meantime. If I can't find anything, he suggested I quit. Which is really insane since there are other options but I feel he suggested I quit so I no longer contribute to my insurance plan and I am left on my own. Basically, the insurance company will have nothing to do with me, which will save them money.
So, the other day, I comment how the office is hot (because someone was cold and cranked up the heat). The manager says she's not hot, it must be me and just left it at that. I was stunned. A few hours later, a few people grumbled about the heat but did nothing. History has shown that if you speak up, you will suffer as a result...and this is from a union shop. However, it's only a union in title. They have no backbone and have no power too.
I have had issues before with the heating in the office and how people on their own crank up the heat whenever they see fit. I have brought a thermometer to work and the temps are in their high 70's to low 80's. The union says they cant enforce the labor code until the office temps reach 87 F.
I told this to my psychologist and I requested that he make a recommendation that I be situated in a more suitably controlled office environment. He declined. He said there is no medical reason he could justify that. I am once again in shock. The physiological and psychological changes that happen as a result of being too warm are not justifiable? I can't work under those conditions. I'm dwelling on this problem and I can't get it out of my head. I o never expected a response from my supervisor considering I had just returned from a years leave of absence. I now know they don't want me back and they hope I crash at work.
If anyone has any suggestions, other than using a desk fan (already have two) which cause me headaches and cause my documents to be scattered all over the desk, I would appreciate it.
Thanks