The other ladies have given you great advice.
I have only one thing to add - have you tried putting ponytails in your hair at night? I know that you said you're unable to braid your hair, so maybe ponytails would be easy enough on your hands?
I had a big problem with tangles in the back of my hair until I started putting my hair in 4 afro puffs for bed (under my satin bonnet).
Hope this helps, and good luck!