I'm going to upset my mother
Why would you upset your mother?
I've lost my temper when I told her that I preferred to live on my own rather than move in with her.
You should care about your mother's feelings. It's important to respect your parents who raised you.
I don't care about her feelings. I'm such a cold-hearted bastard.
Then you should learn to be more warm hearted. Being cold hearted will turn people away and you will end up alone.