Generalities:

Guilt complex

Causes:

Being exposed to too much criticism or demand either from oneself or from others can create a guilt complex. Many times this happens in childhood and may be accompanied by a feeling of shame: of not being good enough, having something intrinsically that makes him "inadequate", being dirty, stupid, weak, and so on.

It can also originate from a traumatic situation such as rape, accident, witnessing a tragic scene as an accident or murder. Situations where the person believes that he could or should have acted differently to avoid the tragedy.