I'm going to yell at my gf and refuse to apologize for it even if that means she will break up with me over that
Isn't that cruel? Why would you insist on yelling at your girlfriend?
I didn't like what she said.
It's not okay to yell at your girlfriend deliberately and not apologize. You should try talking to her reasonably. She will be more receptive to what you have to say if you're respectful.
I don't plan to change anything.
I'm just trying to tell you that it can be really hurtful to her if you yell at her like that. Don't you love her, and want her to be happy? How about just relaxing when you're frustrated, and then coming back to tell her how you feel?