How do I move on?

My “friends” pulled a pretty realistic prank on me that one of our teachers had died. They had told me before class had started and before the sub told us anything. These are my closest friends and they know that I’m sensitive to this kind of stuff. Being the sensitive person I am, I started crying and the people around me were worried and confused. When they asked what had happened I realized that our teacher wasn’t actually dead. My friends were like “Omg did you actually believe us?!” And laughed it off. When I didn’t want to talk to them they asked if I was really that mad about a “little joke”. It’s been 3 days since then, and I can’t stop randomly crying. I’ve already decided that I don’t want to be friends with these people anymore, but how do I forget about the joke?