Need some Help (no lights): not '67-'72 but you guys know alot

[arkracing]

I have a car that has no lights. All the fuses are good. My wife said that last night she was driving and flashed the high beams @ someone cause they had thiers on. As soon as she did that she lost the lowbeams (she thought all other lights were working ok). She put the highbeams on and drove to her parents house and stayed there for the night (I was out of town). She drove home today in the daylight. I just went out to check it out - I turned the lights on and they Worked - flipped the Highbeams on and they shut off EVERYTHING! Tail, Markers, etc. Blinkers work, flashers work. The Highbeam light on the dash comes on if you hit the switch to the "momentary position" but when you flip it to the "Highbeam on position" there is still no lights. So now I have nothing

All the fuses are good - Underhood & Under dash. Everything else seems to work fine.

I'm thinking headlight switch??? - Any other ideas?