I've had this "internal convo" so many times...what would I say to teenage me if I had the chance? It would look something like this...
I know you think life ends at 18. Let me assure you, it does not - it only begins. You are in the middle of the most dramatic, crazy, emotional years of your life right now. It isn't always this way, I promise. Emotions will calm, become stable, and you will begin to learn about the most amazing emotions in the next few years - unconditional love, true happiness, and passion for life, just to name a few.
In high school, being the most popular, the most beautiful, and the most talented seems like everything. These aren't everything, I promise. Life is about finding your passion, surrounding yourself with those that love you and that you love, waking up excited to start each new day. It took work for me to accomplish all of these things, but I finally feel like I have...and it's better than I ever imagined.
You think you're going to graduate high school and go into a job that you love. You will, but it's so far from what you are thinking. It takes you a few years to figure this out, but you will...and those years that it took you aren't in vain. They reassure you that where you are, here, 12 years later is the perfect place for you. But, be true to what you love and what excites you, rather than what you think everybody else wants out of you.