Car Will Not Start problems of the 2010 Buick Enclave

The power steering on my 2010 Buick Enclave stopped working slowly. I was almost unable to turn the steering wheel at all. Not only was the power steering a problem, but the "service airbag" light had been on for a couple of months. I took the car to a local dealership's service dept & told the service rep that my power steering was not working. I also asked the airbag recall be done on my car. The service rep advised me there were 2 recalls required, but the second if the 2 required she order parts. I left the car, a diagnostic was done ($119. 50) & I was told the power steering pump & steering rack would cost approximately $2,000. I had the car towed to a repair shop I have used for years and who I trust. This repair shop replaced the power steering pump, cleaned metal out of the system & filled the system in power steering fluid ($724. 00). I picked the car up & it seemed ok. Within a couple of days, the power steering failed again. This time the car had dumped power steering fluid. I had the car towed back to the same repair shop. They repaired the burst line & I picked up the car, which drove as it had before the problems began. I parked my car in my driveway with the front of the car below the rear of the car on a downward incline. The next morning, the car would not start. I called aaa and paid $90 to have the car towed again. The car was towed on a flatbed and when it arrived at the shop, it started immediately. I told the repair shop rep to park the car as I had, on an incline with the front lowered, overnight. He did & it would not start the next morning. He told me he rolled the car off of the incline & it started promptly. He suggested I take the car back to the dealer for the 2nd recall. I picked the car up and drove it for 2 days. It sounded bad, the steering stuck & the steering started making loud grinding noises & it smelled like something burning.