Power Steering Pump problems of the 2001 BMW 325

In the events leading up to the failure, the car had been parked for 1 hour. I got into the car, put the key in the ignition and noticed the steering wheel felt very tight. I turned the car off and then turned it back on, I tried to reverse the car and started to back out of the parking spot but was able to turn the wheel while backing out of the spot, meanwhile I was using all of my strength but then I could not turn the wheel and got stuck in the middle of the road and I had to have a by-stander help push the car to a parking lot while I tried to turn the wheel. The complaint is that if this problem turns out to be the power steering pump this will be the 3rd time I have had it replaced in this car and I believe that is unheard of! I have this replaced at least 1 time a year which seems excessive. Each time this happens that car has been completely fine and suddenly the power steering will go, it is very scary and I am afraid that it will happen one day while I am in the middle of driving.