There's only one thing you should think of if someone says that again to you: OPINION. Yes, it's just their opinion. They believe what they think is true. Everyone's entitled to have an opinion, but it doesn't mean that what they believe is always true.
We have what we call individual differences. The Earth is round (figurative language). We live in different parts of the world. We grew from different environments, different cultures, different customs, etc. You might be able a thing that other people can not do. You might eat a food that other people can not eat. There will always be differences. Even the identical twins are not identical.
My point here is this: it's already a nature of people to be radical. We think differently. Someone will say that you are ugly, but it doesn't mean that you should believe what he said. As long as you are not hurting anyone, just do what you need to do. Believe in yourself. Take other's opinions as your fuel to be a better person and a better member of your society.