Beauty is not something that can be achieved or lost. It is not a state of being - it is being. It is pain and love, sunsets and sunrises. It is the experience of learning, growing, then changing. Life is not beautiful - life is beauty.
Therefore, our outsides are not, in fact, outsides. Beauty cannot be contained, for it permeates all things. Once that is accepted, our physical bodies then become tools for experiencing beauty - that is to say, for experiencing life, others, and ourselves.
We should not worry about wanting to feel beautiful. We are the very essence of beauty regardless of the appearance of our tools. Those who would judge the worth of a tool on its appearance rather than how well it functions will never know beauty. They have closed their minds to learning, growth, and change. They have closed their minds to life.
You are not like them.