Need Your Help

I have a 89 Mazda MX-6 Automatic 2.2 which is really starting to make me pretty nuts right now, I had a problem yesterday which almost got me hurt on the highway i was driving along and all of a sudden the car shuts off, i had head lights and interior lights but no insterment lights and clock didnt work. Its strange driving along at 70 and the car shuts off like you turn the key off, it didnt so nothing at all no sounds just shut offf like i said i turned the key off, I played with Ign switch and shiffted into drive and pasrk and so on and after 5 minutes it started, Whats up with that?? Could it be my ign switch, Please help me i already am totally disabled i dont want to get killed now