Life is beautiful, so you should live it beautifully. You're just fifteen years old. It is not your fault! Nobody is perfect and no one will. Your age is the age of making mistakes, so it's okay to make mistake. It is not your responsibilities. "You could have prevent it." is not meant to be. Not knowing something bad will happen is not your fault. So don't take responsible about it.
You're just sixteen years old. You can make mistake! Mistake is inevitable. Being afraid is normal. It's okay to have weaknesses. It's okay to fail. It's not your fault. Don't think that you have no right to make mistakes. You can make mistakes.
You're just seventeen years old. Don't pretend you can be perfect. Nobody is perfect. You can make wrong choices. You can change your mind. You can make mistakes. You can be understood. You can be forgiven.
You're just eighteen years old. Not because they failed, you have to be responsible for the rest. You're not at fault. Don't take responsible. You can make mistakes. Believe in yourself. Don't live for them. Don't succeed in life because you have to for them. Don't cry because you're afraid to fail them. Don't run because you're mad you'll disappoint them. Don't lose yourself because you can't find the person they want you to be.
You're just nineteen years old. Dont wish to die because you feel like you'll cause them dead if you fail. Don't cry at night because you're afraid of your reality and nightmares. Don't hide somewhere because you're ashamed of what you have become. Succeed because you want to, for yourself. Don't take responsible for them. You're just you. It's okay to make mistakes. Be afraid. Have weaknesses. Cry. Fail. It's okay to be you. **Be You.
Because every one of us had a past self that are full of regrets. And I hope by writing this, I am letting my younger self flee from any guilt and regrets.