I'm going to support my friend who has cheated on her boyfriend
Why do you feel like supporting her?
She is my friend and I'm not close to him.
I understand that since you know her and not him. It's expected to be more loyal to the ones you know.
I'm only going to support her, I won't stick up for her.
I am glad you have loyalty for your friends. You shouldn't feel the need to make excuses for her behaviors. But be there to listen to her problems.