Automatic Transmission Torque Converter problems of the 2015 Buick Enclave

I purchased this vehicle September 2015 from carmax in charlottesville, va. Since that purchase, I have kept up all the routine mantainance on a schedule from oil changes, all fluids, tire rotations. April 21, 2016, my first rather large expense, "engine check'. I am hearing a noise in the front end. Warranty paid a portion of this issue and I paid the balance. The service department installed n strut, n nut, insulators and bearings. And the driver seat trim cracked and broke. (1st time); next issue is a total warranty issue that included replacing the torque converter. I advised them the engine was skipping and the car would slow down. They installed a converter gaskets, hose and 12 qts of fluid. 1/27/18. I advised them again of a leak from what I thought was the engine. At that time, they advised it was a vapor leak from the exhust pipe. Also. . The driver seat outer panel broke again, they replaced. And now, 4/28/18, they are telling me the drive shaft has to be replaced at a cost to me of over $2500 +. Now. Yes, I am concerned. This should not be happening to a relatively newer vehicle. . One would not think. My Enclave has 104k miles on her currently. This vehicle was purchased for my weekend visits with my daugher and grandchildren. To replace my 2000 Ford explorer. And now, I am feeling safer in my Ford explorer. I have never had to have any kind of work done on that vehicle, except for routine maintainance. And she is still running as great as ever. What can gm do for me and my 2012 Buick Enclave. I am losing my faith in this vehicle. Please help. Thank you for your time. I hope I don't end up having to pay for this issue.