What should you say if your friends called you ugly?

Personally, I would find new friends... But that doesn't always work and it might be considered a sign of weakness by these so called friends and their behavior would continue. If they say nasty things like that to you and it really bothers you, try and confront them about it. Ask them why they think such things of you. People should like you for who you are and not what you look like, and even though they have their own opinion, its not necessarily true for everyone. Beauty is in the eye of the beholder, and they are the mentally ugly ones for putting you down like that.