1997 Chevy Silverado Wheel fell off last month, showing sig

About two months ago my ABS light came on on my Chevy K1500. I went through the normal steps; changed the brakes checked the fluid check the caliper. Light was still on, decided to take to garage. On my way there my steering became erratic and my front passanger side wheel detached from the axel, the spindle was still attached to the wheel. I asked my mechanic if the bearing blew out, he could not tell. About 1500 dollars later the truck is back on the road. Now the ABS light is back on. Is the same problem going to occur, was it the wheel bearing, or is there an axel clip that might have fallen off?