I don't have much info to share about frozen shoulder syndrome, but I have heard that it is extremely painful. Sorry to hear this is what you may have. I've also read, though, that it can be completely cured--but as you know, it takes some time. Hope you get some kind of relief in the meantime. I doubt whether you would want to do physical therapy at this point anyway--it would probably be too painful and not very productive.
I know where you're coming from. I've had frozen shoulder in both shoulders, thank goodness not at the same time though! It's quite a few years ago now but I still remember it well. Left shoulder happened after I had surgery...what they did to my arm is beyond me but soon afterwards my shoulder froze up. They pretty much had me going for therapy right away and it was excruciating. I did therapy for six weeks. One cortisone shot not only did nothing for the pain but made the pain worse...ran all the way down my arm after that shot. Second shot a week later took the radiating pain down my arm away but did nothing for my shoulder. I had a prescription for NAPROSYN and I don't think it made a blind bit of difference. I basically had to grin & bear it. I slept with pillows under arm. I did the exercises at home but overall it just seemed to be a matter of time and it got better over a period of a year. Putting a bra on was a bear...would hook it from front, slide it around but getting the arm through the strap...even thinking about it now makes me cringe.
The right shoulder froze up about six years later...I didn't bother going to Dr. I just kept moving it as much as possible. I'm right handed so it was a b***h, especially in the bathroom, if you get my drift. Pure agony. I just used OTC pain reliever and over a period of about a year it unfroze. I did the ROM exercises that had been prescribed the first time. You have to keep moving, I know it's hard. I have two sisters that also suffered from this, one of them had the manipulation under anesthesia the other had PT. The manipulated one was better a lot faster than my other sister or myself. I found it rather bizzare that we all suffered from this ailment.
My ROM after all these years isn't the best but I can raise my arms over my head and put my arms behind my back. Sorry that mine isn't a happy tale. I hope you have better success and a speedy recovery.
Take care, hang in there girl!