Each of us has dreams every night, of which, none of us, can remember all of our dreams, but virtually all of us, can remember at least some of our dreams, some of the time; of which, not terribly surprising, those dreams that have a lot of emotional impact have a strong tendency to typically be the dreams that we remember the most. That said, those dreams that make us overly anxious, or fearful, or upset, are usually described as nightmares; and while it is true that a nightmare is not reality, for we are in a dream state, it can often feel so real to us, that the experience of that nightmare can seriously affect our emotional state upon our waking up from such.
While there are a lot of reasons of why a nightmare might so occur, such as from the lack of consistently good sleep, a poor diet, drugs, guilt, stress, and things of that sort – it has to be acknowledged that people that have stressful lives or are in an especially stressful situation are in place in which this thus often creates anxiety -- and anxiety has a way of carrying over into our lives, even when we are trying our best to keep our minds focused upon something else or upon some other activity so as to alleviate that constant nagging feeling of anxiety.
The thing about dreams, or nightmares, for that matter, is that all of this originates in our mind – which signifies that the dreams and nightmares that we have, are ours to own. This means to the degree that we care not to remember or to dwell upon our own dreams, is a conscious choice which we control. In short, the fact of the matter is that these are our dreams, which should send a signal to us, that it might well be in our best interests to want to pay attention to our dreams, good or bad, so that we can try to figure out the message of what we have so dreamt. Those then that desire to learn from their dreams, thus make it their point to have some sort of memory aid by their nightstand, such as a voice recorder, or pen and paper, and further they impress upon their minds before they reach that sleep state that they so desire to remember their dreams.
For those, then, that seem to suffer from an inordinate amount of nightmares, this should be best seen as an opportunity to try to figure out the message of the nightmare and then thus to correct what needs to be corrected in the mindset and the actions, so of, subsequently made. While a nightmare might present itself for a multitude of reasons, one of those seminal reasons, has got to be seen as a warning to us, that not all is right, which is why we feel that anxiety that nags at us. Each of us can try to escape facing what we need to face, but in our repose, we so find, that what we will not deal with consciously and proactively in the present, is presented to us as a nightmare so that we will be reminded that our house is not in order, and that we best do what we need to do to achieve that necessary order, or at least try to.