I think it's better if I bow out of theis MM.
None of what you say is an indication of not having enough/any milk, either in you or your friend (including the squeezing - no matter how good you are at it! Your baby does not get milk by squeezing).
Skim milk and full fat milk? Fat content of mothers' milk does not vary at all with her diet - there is a ton of research on this. Fat content varies with the degree of fullness of the breast. Fuller breast = less fat content in milk. Breast with less milk in = more fat content in milk.
With milk production, there is a lot of vetinary research, much of which applies to all mammals, including us. We have known for some time what the variables are in fat content, and it has nothing to do with the mummy mammal's diet or how often she rests. That goes for cows, goats and us
Truly, rest has nothing to do with it at all - only in so far as if you are running round, you are deffo not on the sofa feeding the baby. And without feeding the baby often, you won't make milk.
I won't post any more on this unless I am asked to. My experience is that people become very attached to powerful ideas, and resist the information that shows they are not well-founded. It doesn't bother me if you have been helped with a protein lunch and a rest with your feet up, mojomummy - it sounds very nice! But as a 'recipe' for bf happiness, it doesn't stand up