Stolen milk and pregnancy (DEFINITE SPOILERS)
First, do not think I am downplaying the boys taking Sethe's milk. That was horrifying and I can't even imagine how humiliated and violated she felt. Even with no actual intercourse it was still a form of rape. What I couldn't figure out is why she fixated specifically on losing her milk. At first I thought it could have been related to the baby's death, but besides the nursing baby being sent ahead already the milk would be replenished in a few hours. Before she got to her she would have had to do whatever the equivalent of expressing was in those days and probably more than once. Did her fixation develop over time to ease her guilt by convincing herself that by taking her milk those men contributed to the baby's death?
When the women came to expel Beloved they already considered her evil, but they seemed truly horrified by her pregnancy. In the movie it doesn't say how long she was there, so I wonder if it had not been long at all and some of the shock and fear was an abnormally advanced pregnancy? That would have added to their belief she was unnatural.