your post touched me. it's so easy for any of us to get to the place where you are. Ive been there, and ocaassionally "visit" there again. We put a lot of hope in people. We form relationships only to have them shattered repeatedly. As I look at Jesus, he too, was disappointed by the relationships in his life. Let me throw this out to you. I wonder if it could be that we put undo expectations on people. For instance, Jesus said, he trusted no man because he knew what was in the heart of man. As human beings we want to see people in a positive light, and what they can do to make our lives better. It's a selfish thing on our part. Because of this, we put high expectations on them.....which they can never meet. We're "flawed", and only Christ can fix it. Yes, we're called to love everyone, but before we can do that, we have to love ourselves. We have to see the creature that God created, and not the person other people have made us. Our parents told us how we should be. Our teachers. Our friends and even our religious people. But only God knows who we are and how we should respond in life.
We've been programmed by so many people in our life, and it's hard to "deprogram". You sound like a very sensitive person which is probably why you are hurt so deeply. Find out who you are. The special person God created. Not the person people have said you are. Don't be angry at those that hurt you. Like Jesus said on the cross about the two men hanging next to him: " Father, forgive them for they know not what they do." The people who hurt you........they don't know what their doing. They're ignorant because they don't know what love is. But neither should you associate with such people who bring you down. And sometimes the people we most hang out with are the ones who hurt us the most. Judas hung out with Jesus, but betrayed him in the end. We can't forget that we're still human and will fall into human behavior and bad character. But you are special and God has a plan for your life; a purpose as you say. He will reveal that purpose. Right now you may be in a time of "preparation". God getting you ready for something. Love yourself.