It is not uncommon to feel that you caused the death even if in reality there is no way you caused the death. Sometimes it is a way to make sense of something that is so overwhelming and lets you feel helpless. If you take responsibility, it is a way to make sense of it. Also feeling that you caused it, is a way to let you not experience the anger you feel that he died. Instead you make him the one who is angry. Remember after a death of someone you love, having all kinds of feelings are common and everyone has them at different times. You are no different than many others who experience a loss of someone who you cared about.