On my mind.

Well...I cannot stop thinking this week about a revelation that my roommate made to me.
I for a very long time have had nightmares...the kind where I wake up screaming and crying. I first noticed when I was living with my brother 5 years ago and I know that it scared him...he would not go to sleep until I was completely out and he would often wake me up in the middle of the night telling me to stop screaming.
I honestly did not think I still was screaming in my sleep, because I haven't waken myself up from doing so for a long time...but my roommate informed me that I am waking her up with my screams.
I cannot get this off my mind the past few days...what am I dreaming about? I know when these dreams started, and I am sure It is still the same issues....all these years later.
Am I really so gaurded that I let my emotions only show in my sleep?
What can I do?
I need to think about this one.