I want to cancel my trip with my friend.
Do you have a good reason for cancelling?
Yes, they're definitely not my friend anymore. No one thought the beach suits me and they all made fun of me like the ugly beast
While situations change, it is still expected to follow through on commitments. Otherwise people will not trust you to do what you said you would.
Fucking bitches. I guess I am going alone.
If you really have a plans you should talk to your friend and try to work through the issue before you flake. Even if you're upset at the moment you'll only escalate the situation more if you purposely upset them.