Why can't I drink milk anymore?

 Why can't I drink milk anymore?

Milk is a nutrient-rich, white liquid food produced by the mammary glands of mammals. It is the primary source of nutrition for infant mammals, before they are able to digest other types of food. Early-lactation milk contains colostrum, which carries the mother's antibodies to its young baby and can reduce the risk of many diseases. It contains many other nutrients including protein and lactose. Inter species consumption of milk is not uncommon, particularly among humans, many of whom consume the milk of other mammals.      
I know that milk is very good for health. But I don't like milk anymore. I do not tolerate its smell or taste. Especially, whenI think about where the milk comes from, the idea drinking it come even more disgusting. 
Why do we have to drink someone's milk?
A cow has to give birth each year to have milk. This is not normal. I'd like more plant milk. But they are much more expensive than cow's milk.
I eat dairy products because I can't give up on them, but I don't drink milk anymore. It makes me sick.