Can I be mad that I didn't hear from my bf?
Why did he not contact you?
Because he's a traitor who should be dead
Relationships are hard so it is understandable that you are going to be mad sometimes when they do something you don't like. It would be better to talk them instead of just staying angry.
You're stupid and I'm going to end it here.
You can be mad but only if someone has really does something like disappoint you unnecessarily.