You may not know it, but there are things that you may be saying to yourself over and over everyday that are becoming the things you believe.
It may have started out as things others have said to you. It may be based upon the conclusions you have drawn from the ways that others have treated you. See if you recognize these:
1) "I believe that deep down, there is something terribly wrong with me."
2) "I believe that at one point, I could have done something about it, but I didn't. It's my fault."
3) "I believe that there is no hope for me."
4) "I believe that other people hate me."
5) "I believe that I am worthless."
6) "I believe that no one else could possibly understand me."
7) "I believe that no one can help me."
8) "I believe that I must die for what I've done and for what I cannot do."
Listen to what you are saying to yourself. Are these the types of things you hear? Ask yourself, "Do I really believe these things, or am I saying these things to myself out of habit and without realizing it?" Either way, if you say these things to yourself enough, they will come to be what you believe.