Shield and lotion
A nipple shield and a lanolin-based lotion might be just the ticket.
The nipple shield is a small, silicone
shield worn over the nipple during breast feeding
to protect it. The lanolin-based lotion will help to protect and restore the skin around the nipple and areola. She should be able to find both at any good store that sells stuff for babies and moms.
Answer assisted by David Miller, Medical Student