Major problem. I own a '94 Honda Civic EX Coupe. My dash lights stopped working yesterday, but only when..?

..I turn on my headlights. When the parking lights are on, everything works fine. In addition to the dash lights, my taillights turn off too since they run off the same relay/fuse. All of the fuses are fine, I pulled and checked every fuse in both the dash box and the engine compartment. No loose wiring, no visible ends. Today, out of nowhere, my power windows decided they didn't want to roll down anymore, and my sunroof wont go back, as well as the SRS dash light staying on continuously when it never has before. On top of all this, I also lost both high and low beams on my left (driver's side) headlight, and the door speakers of my very overpriced stereo system stopped working but the back two, both subs, and the amp all work fantastically. I have limited knowledge of relays and most car maintenance, and even my friend studying to become an auto tech can't seem to find the problem. His only guess is that maybe the ECU is finally going to crap, but I'd never had this problem until after we checked all the wiring and fuses. Does ANYBODY know what just happened to my car??? (As a side note, since I'm not sure if this has anything to do with my problems, I have an aftermarket alarm system from Bicron. He suspected before that maybe the alarm was shorting out my lighting since its wired into the same relay.)