Nobody truly prepares you for the cruel experiences that you will face when you get older. They never warn you that people will be harsh, or that you will begin to slowly despise everything great in yourself. You will stop getting excited over things that bring you joy - you'll talk a little quieter, maybe laugh a little less. The idea of anyone loving you when you can't even love yourself will seem unrealistic.
However, you are not labeled by other people's opinions of you. You are not a number on a scale, or the brand of clothing you wear. You're not defined by that boy who never loved you or the parent who wasn't there for you. You are an amazing human being who is composed of stars and galaxies. There are wars inside yourself every day that you are constantly conquering.
For this reason, don't say maybe if you want to say no, don't settle for less than you deserve, and most importantly, do not let people allow you to become a secondary character in your own story. The minute the boy you like suggests you change who you are - run for the hills. Your personality is golden, your style shares a story, and you should not have to revise your fairy tail ending to get the boy who doesn't appreciate your perfectly imperfect flaws. Leave behind anyone who doesn't make your friendship a two-way street. Your passion for dancing silly down the sidewalks and binge watching chick flicks should never make you feel embarrassed. Overcome the hurt from the parent who left you feeling unlovable and unimportant. They will be shocked to realize they have created a strong, independent person who has learned to save themselves when times get tough.
You deserve to love yourself - stretch marks, acne, wonky smiles and all. Laugh as loud as you want, cry when you are upset, and rise above the people who don't provide you with an important place in their lives. Live in the moment and the positive outcomes will begin to flow in. You will begin surrounding yourself with people who love you and situations that will bring you nothing but happiness. Things won't always be easy and people won't always be willing to stay, but loving yourself makes it so much easier to define your own worth and focus much less on the things that don't go the way you planned. You only have one life to live, it would be a shame if you spent it trying to make everyone else happy.