Your boobs will hurt during pregnancy, it's because the hormones in your system are causing them to grow and change in preparation for making milk.

The best things you can do for preparation of breastfeeding is....join ABA, get some REALLY good books on breastfeeding and attend some BFing meetings/clubs with oher ladies and watch them feeding. Learning good technique is the number one thing you can do to avoid pain and damage from BFing. Tough nipples don't help (nature designed this system way back when and i don't think neolithic ladies rubbed rocks on their boobs!) and you will only have a miserable time aggravating already-sensitive nipples during pregnancy.

There is some pain which isn't avoidable - i have flat nipples and the first few seconds of a feed for the first few days were a litte painful as the nipple was stretched out into the back of DD's mouth. I learned to ease it by stretching my nipple by hand before attaching DD and also by expressing a bit of milk off if the breast was very full. Other pain - that of poor attachment, is completely avoidable with good technique.

Bx