I have had daymares too. I used to also call them dayscreams, because my actual emotional state would be affected (including crying on the way out). And i kindof just deal with them. They play out, take over for a few minutes and at some point i shake myself out, usually while gasping sharply, and actually shaking my head. I get them at random points of the day, and they are always related to my immediate surroundings. sometimes i will detail the [events] in a journal entry, to distance myself from it. Sometimes I will ask myself what i can learn from the events. I'm constantly gathering information on stress and anxiety, and i assume theyre related to that. In all my gathering I have never found anything conclusive on the subject of daymares though.

They are probably related to panic, anxiety, depression, and stress.
They are possibly a problem-sorting mechanism, like dreams.
They are possibly a venting mechanism, especially if you come out of them crying. I have read things in the past that basically say that the purpose of crying is to release toxins from your body that build up from stress.

As for making them go away, it may very well require that a specified portion of each day is dedicated to various coping mechanisms. In my experience, they become duller while i listen to music. Hope this helps.