I'm not going to keep facetiming
Are you going to stop facetiming because you're mad at a friend?
Yes, I'm mad at my friend
It's okay if you don't want to facetime with a friend who you're upset with. It might be good to take some time to yourself to cool down, and then later talk to the friend about what upset you.
I am going to keep doing it. I'm just not going to talk to her.
You should just be honest and upfront with your friend. If you keep facetiming them while upset they might pick up off your vibe. This could make your conversations really awkward.