IMO, we are not responsible for thoughts or dreams which we had no play in forming. All kinds of random and unusual stuff can pop into our minds. The problem is in entertaining the negative thoughts. If we think of thoughts and dreams the way we think of temptation, it is the same. It is only when we act on these things that we become responsible for our actions. However, even dwelling on a specific negative thought may result in a change of mental or behavioral norms. In the case of various mental illness, one may not be able to discern fantasy from reality, or at another level, be plagued with obsessive negative thought which leads to, or can be a result of, depression. Normally, we can dismiss strange thoughts and they go away, but sometimes they hang around and can afflict our thinking as we dwell on them too long. We are not responsible for the thoughts or dreams, but we are responsible for how we handle them.