Why do Dreams Recurr for Anyone?

Your unconcious self is sending you a message that is demanding you to understand it and until you do it will never stop recurring.
Anytime you have a dream, it contains a message, that is the purpose of them. But most of the time you won't remember having one, and if you do it's because you woke up right in the middle of it. Most of the time you don't remember having one at all during the night. But with a recurring dream, you have them because the message is so important that its never ending and keeps recurring. Since the dream is that powerful, it will keep recurring until you notice what the message is, stop pushing it away and trying to ignore it and do something about it.
Since the dream is recurring and is trying to get your attention really bad, it will usually be a bad dream or a nightmare therefore making you have a better memory of it so you DO NOT forget it.
Like childrens nightmares, recurring dreams are common and are usually caused by a certain life situation, changing phase, or a problem that is never ending. Sometimes they can be looked at as a weakness in something you're doing, fear in something or someone, or you being unable to cope with something that happened/happening. Unlike the average childrens nightmare (couple times a month), recurring dreams can happen as often as every night, once a week, or once a month.

http://www.dreammoods.com/dreaminformation/dreamtypes/recurringdreams.htm