The context of the following conversation is Even though it was slightly spoiled, Aubrey drank the milk anyway.:
Aubrey says Do you know if this milk is still good?.
The friend responds I think it is, but there is a chance it is lightly spoiled..
Aubrey responds Nasty, it is a little bit spoiled..
The friend responds Then why're you still drinking it?.
Aubrey responds Because we have no other milk..