Hi,
I hope you will take this in the spirit with which it is genuinely meant. Occasionally some of us have body parts that don't work properly and in rare cases not at all. Breasts are the same. It's true, sometimes they just don't work. There is absolutely no need to feel guilty, any more than if you had kidneys that didn't work or lungs or legs. I guess that the difficulty comes because, surrounding breastfeeding there are layers of mismanagement and misinformation. Breastfeeding is really important for the health of mothers and babies, and it would be irresponsible for health workers to pretend it's not important and it doesn't matter. A skilled midwife or lactation consultant should be able to examine your breasts and at least give you some idea as to the level hypoplasia. Your GP seems to have been supportive - did she examine your breasts? Lactose intolerance is a little different. It is extemely rare for human babies to be lactose intolerant. Human babies produce lactase, the enzyme that digests lactose, as babies and young children. In many ethnic groups people stop producing this enzyme as they pass the normal age of weaning. In many cultures adults don't drink milk - not human milk, and not the milk of another animal after childhood. Many people, including health professionals mix up cows milk protein intolerance with lactose intolerance. It can be hard to get a true picture going through past diagnoses. They may not have been accurate.
You are wise to prepare for both eventaulities and it's normal to experience mixed emotions when your choices are potentially taken away. I have worked with many women with hypoplasia and almost all have been able to breastfeed to some extent. There is more to a breastfeeding relationship - and indeed more to mothering than just the milk. Breastfeeding's not a race or a competition. I think you will find that you will get a lot of genuine support from people, whether they know your situation or not.
Barb
(who myself comp fed one child and fully bottle fed another for nutrition and suckled her without producing milk)