Power Steering Failed problems of the 2012 Chevrolet Sonic

Major concern: my power steering failed. The dealer said the power steering column needed to be replaced ($1,300). The car has high mileage (excess of 150,000). I have had several cars with similar mileage but never had the power steering fail. Since this is electronic steering there doesn't appear to be any warning/no preventative maintenance. Fortunately I was not on the highway at the time this occurred but in the driveway after having driven several hours the same day. We checked for relays in the fuse box but none are marked for the power steering. There were at least two previous times when backing out of my driveway that the power steering locked up but then started working fine. Dealer could not find the problem for the first two incidents. My car has been sitting in my driveway since June 2015 because I didn't feel safe driving if even it was fixed. I've always owned gm vehicles (for 36 years) but the lack of concern about this problem prompted me to purchase a Subaru. At the time of the steering failure I still owed 2 years on my loan. The second problem which I've complained about since the car was new was the transmission. There was always slow response when pulling away from a stop. It worsened after the car had been driven several hours. Again, nothing was diagnosed.