There's never a need to compare yourself to anyone else. God gives each of us a very special and unique set of abilities and skills. They are ours alone. My potential in the gym is completely different from yours. It's phony trying to be like someone else. And not much fun either.
If there's one truth I want to pass on to my grandkids it's this: True satisfaction in life comes when you realize you are a unique creation of God. Get comfortable in your own looks, personality, and abilities. Learn to enjoy your own very special corner of the universe. Most of all, realize that when God made you, he was pleased.
Instead of comparing yourself to other people, compare yourself to yourself. Observe how much you have grown, the things you have achieved, the obstacles you have overcome, and the progress you have made in reaching your God-given potential. This will enable you to think good about yourself without thinking less of others.