Immri, while I appreciate what you are saying about "extreme thinking" and the paranoia we have when we use alcohol, I think that in this case it would have been wiser to set up a boundary in the first place.
If you go to bed at 9.30, unless there is a fire or someone is dependent on you, it's really not OK for someone to come in and turn on the light at 11. You have a right to lay in bed dozing, listening to music, sleeping, reading or whatever else without someone interrupting you.
I'd lay down a few ground rules (boundaries) with my house mates if I were you.
That said I get it on the reactions, we tend to be so extreme when using our DOC.