Gosh, I hate to encourage you (I'm sure that complete r&r is best, but I know how we are...)
You might want to put aero-bars on your trainer. It might give you more riding options that put less pressure on your shoulder. I've added them to help with trigger finger symptoms, so I'm not putting pressure on my hands. But, you really should take it easy!

Oh - I put on some of my sports bras from the bottom up - it might be easier than over the top...