Other Fuel System Pump problems of the 2013 Buick Enclave

I purchased a new Buick Enclave in 2013. At 116,000 miles, my car all of sudden decelerated while on the highway. I was able to get off the road but it would not accelerate past 35 mph. I managed to get it home by taking street side. When I attempted to take into the dealer the next day, it would start, sputter and then cut off. I had it towed to the dealer. The dealer advised me there was an issue with the high pressure fuel pump. The dealer advised me when they attempted to install, it broke. I looked on line and read that gm has been made aware of issues with the high pressure fuel pumps in its Buicks, among other cars. I called the gm complaint line. Gm advised me that because my car was outside of warranty they would not pay for the repair. My concern is that if they knew of the issue or now have reason to know of the issue, why would gm not be required to mitigate damage and pay for the repair or some portion thereof.