Tore mine in 2006, at work. First time experience with a "nerve block." Had the surgery, went home, was OK, till the freakin nerve block wore off, then indescribable pain. Couldn't lie in bed, had to wear this appliance, that resembled a love seat, around my neck, and rest my arm on. So I obviously got thru it. Have the same probs in bed, as you describe.
8 years later, went in to have some MRI confirmed bone chips removed. When I woke up, they told me it was a rotator cuff. Just wanted to end it all then! Since it was not a result of an injury, maybe just wore out, the recovery was a piece of cake. No love seat to wear, and very minor pain.