So, when you are sad and doubting yourself; when you wonder why you are here; when you wonder if you are doing enough or if you are perfect enough or if you are a failure, remember this:
You are not a mistake. The odds against your being here are enormous. The fact that you exist demonstrates that you were meant to be. So be at peace. Whatever your worries, be at peace. Whatever your fears are, be at peace. You are here for a reason and your life matters.
Live. Know. Be.