Day 04: Five things I would tell my 16-year old self

1. Don't think about things in terms of "good enough" or "inadequacy". Everything is a lesson to be learned (or at least a memory to be made and look back on), and these are the lessons you must learn in your life; these are the days that must happen to you. You are simply not 'right' for something (or someone), but don't think that that means you are insufficient. Keep moving, because you are getting closer to what (and whom) you are meant for. Life and life choices can just be processes of elimination sometimes.
2. Save yourself for someone who deserves to know you that intimately. Don't judge other girls who do otherwise. It's their body and their choice, just as it is your body and your choice. Sex will be much more enjoyable and meaningful this way for you, though, and it will cement the distinction between whomsoever you choose to be with and the others that aren't right for you. If anybody incessantly tries to put you down for it or even change your mind, tell them to go fuck themselves. Don't give yourself away to make a boy stay or because you are afraid he won't like you otherwise. You can do better than that. 'No' means 'no,' by the way. Don't ever let someone make you feel guilty just because you know what you want (or don't want) for yourself.
3. Look into majoring in marine biology or astronomy, not economics and/or business. BUT do retain a music minor; you'll make some of your best friends this way. 
4. You will appreciate your mother much more and actually miss her upon moving out of her house. Cherish your time with her, even when she's temperamental. Especially when she's temperamental. Remember that her behavior finds root in her care for you. If she didn't yell at you, discipline you, and make you feel like shit about your bad choices, it would mean she doesn't genuinely care about you; be thankful, then, that she does, because you will know many people who have indifferent or even deceased parents. Furthermore, she is allowed to be selfish and self-centered and ignorant and oblivious. She's not just your mother. She's human, just like you and everybody else that makes mistakes.
5. There will be times when you are completely alone... suffocatingly, asphyxiatingly, excruciatingly, hopelessly, helplessly alone. People can't always be there for you, despite how many friends you have. They have their own issues to deal with, and you can also be overbearing sometimes. Don't take it personally, though. Remember that people can have moments of selfishness and inconsiderateness that has more to do with them than with you. But other people simply will abandon you, flake out on you, turn on you, refuse to help you, or otherwise make you realize that you've had the wrong people in your life. These people had to be removed from your life to make room for better people--the ones that understand you and can listen to your stories over and over again, the ones that will support you even if they don't agree with your choices, the ones that are here to stay rather than just be a temporary band-aid on some niche in your life. Some people leave because they can't bother to stay in touch; don't take it personally.