Question: Can you get breast cancer from things you do to your breasts, like wearing a bra all the time, or when your partner caresses them?
Answer: No, you cannot get breast cancer from these things. What you wear and how your breasts are touched do not affect your risk for breast cancer.
But if you feel uncomfortable with the way your partner handles your breasts, you need to share that with him or her. It's important for you to be intimate in ways that feel good for you.
You can read a detailed discussion on the actual risk factors for breast cancer.