Jessica Anne you are 16 and stupid, accept it. Allow others to help you and don't think that everything others say is to criticize you. I know you are self conscience, but everyone is not out to get you. Show those closest to you how much you love them. Don't just expect for them to know. Even worse don't push them away because of your fears. Trust me you will regret it when they are gone and you never have as much time with them as you think you will.
Stop hanging out with all those people that bring you down and make you do stupid things. You think they are your friends, but they really aren't. They are using you for so many different things. If you would put the weed down for a second you would be able to see that. On the subject... GO TO THE DOCTOR. You know you don't feel right and are never happy. Talk to someone. You have been through so much in your life and I know you claim that you are more mature than others and have moved passed everything, but you my love are a liar, and a good one at that. You need help, so far nothing you have tried has worked.
Love will come for you one day. You don't have to look to guys to make you feel worthy. Be yourself you are adorable and really funny! Also do your homework. You could have passed that Algebra class if you would have tried.
Be nice to your Grandmother. Yes she is hateful and opinionated most of the time but she loves you in her own special. She grew up in a different time and doesn't understand. She is also dealing with a lot of the same things you are, so take it easy on her. It will also make it so much easier on Granddaddy.
Jessica you will make so many mistakes and some of them will affect you for the rest of your life. But I am here to tell you, don't give up, it gets better. You will go on to get your Master's in Social Work, find the love of you life, and have the most amazing friends you could ever imagine. I love you so much and wish I could turn back time to help you, but it's all up to you!