Must be lactose intolerant....?
Sounds like lactose intolerance. Skim milk has more lactose than cottage cheese, so some people can tolerate cottage cheese and things like yogurt but not actual milk.
You can use soy milk instead or buy Lactaid brand milk. Lactaid brand milk has the enzyme lactase added to it, which helps you digest the lactose. Many people that are lactose intolerant can also tolerate raw milk, because milk naturally has plenty of lactase in it, it's just that pasteurizing milk destroys the lactase, so then it's harder to digest the lactose.
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