Hi Frogga,
It is an awful problem to have

My skin is a constant source of concern for me too and up to this point have not been able to find anything in the long term that works.I am so sorry that this has been added to your already intolerable situation.

With the skin being so fragile sometime the vigorous rubbing and massaging can be detrimental to the skin integrity. In fact where Pressure area care in nursing used to involve frequent massages with all sorts of lotions and potions it is not done anymore as they were finding that just changing position was the best saviour for skin.
When your carers wash you I would not use soap as that can be worse for your skin than not touching it at all. Massaging with some very natural oil product like olive oil maybe better perhaps on alternate days.
I do believe that sheepskins (as long as you have no allergy to wool) might be your best option. There are some special splints now available for people to sleep in that are like those blow up splints used for fractures--this keeps any pressure off your skin for as long as you can tolerate them.
I probably haven't told you anything you don't already know but I DO wish I could help you
Love Tayla
Frogga,
PS- Any Vet or farm supply will have the "udder cream" We use it here often on sore human nipples too.