I'm sorry to hear that. I can relate. Even after having spine surgery, my bra still bothers me; however, it doesn't cause me pain, just discomfort. I've even tried changing bra sizes to make it looser aroud my back, which does help. Are you actually feeling pain or is it discomfort? Do you have any metal implantation at all? When was the last time your scoliosis was checked? There's the possibility that this is a sign of it progressing. I've lived in both warm and cold weather and the cold weather didn't bother me more, which is why I ask about your check-up.
Do you exercise your back or get massages ever? These things can help. Answer some of my questions and maybe I can give you better insight.