This is your permanent and unshakable identity: You are God's beloved. Matthew 3:17 - "We are the beloved sons and daughters of God just as Jesus is the Beloved Son" (Henri Nouwen) SO LOVE LOVE LOVE THIS!
Ask yourself this when someone says you can't do it. What's holding you back? Exactly. Nothing but them and you, but only because you are letting them.
Dear Self. You know what they say about perfectionism...don't you? Why you don't have to be perfect, and in fact it's necessary that you don't try to be.