How about you list down 10 things that you would like to change about yourself, pick one at a time and try to practice it for a week and see how you feel about the change?
You are not useless you have a purpose and that is why you're here
God has given you the gift of life, he's given you an amazing family and they would never ever think that you are useless to them
Your insecurities only make you a stronger person because then you start reaching for a better you
And not only that but you are perfectly perfect in your own ways and that should tell you that you shouldn't change for the world