I think, because of our childhood histories of abuse, it's possible to unconsciously continue to put ourselves into situations where we are likely to be retraumatized. That's one reason why it's fairly common for abused kids to become adults who marry someone who abuses them. We unconsciously recreate familiar patterns until we learn something different, but in order to learn something different, first we have to become aware of what those unconscious patterns are. So... in a way, we actually can indirectly "cause" our own trauma by remaining in or continuing to put ourselves in potentially harmful environments or relationships. That doesn't make us at all responsible for what someone else does to us, but as adults we are responsible for keeping ourselves as safe as possible, and we can't do that by recreating unconscious patterns of behavior that put us at risk.