Sarah, sorry to hear you have had to struggle with your shoulders. I am always looking for new things to help with my wrist pain and a couple of weeks ago I stumbled across this website talking about the work of Dr John Sarno. http://podolsky.everybody.org/rsi/
It rang so many bells with me that bought the book “The mindbody prescription” It was quite cheap on Amazon. I’m beginning to apply his theories and for the first time in a year and a half my pain has reduced. It’s early days but it might be worth a look.
Good luck.