Reddit, what company/brand were you once very loyal to, then all of a sudden let you down?

I have flown on Star Alliance (United, US Airways, Continental, SAS, Turkish Airways, etc) airlines for the past 5 years that I have traveled for my job. I flew over 50K miles each year and became a status member, and receiving access to all their lounges in the international destinations. Never in my 5 years of constant flying, had I ever had a problem with any of the Star Alliance airlines. I preached Star Alliance to all my friends, and was a huge supporter.

Until....Sunday night. US Airways really failed me. I had a flight out of LGA to OMA with a layover in CLT. The flight to LGA to OMA was delayed for maybe 15 minutes and therefore it was going to cause me to miss my connection in CLT. I went to the counter to get rebooked, when the US Airways rep was the rudest most inconsiderate and most unhelpful person I have ever come across in my entire life. He had no idea what he was doing, not giving me any flight options, meanwhile as he is typing in his computer, I am on my phone rebooking my flight myself. He assured me that my bags had been taken off the flight and I could go retrieve them at baggage claim. Off I went to go get my bags.....or so I thought. Bags, NOT THERE. I go on my new flight, again, bags are still not at my destination. Filed a claim with Delta, who I rebooked through, who said that they would work with US Airways to deliever me my bags to my hotel. My bags are still not here, and US Airways have been the least helpful in this whole ordeal.

Because of this, I am putting my foot down. No more Star Alliance connecting flights, no more US Airways. The alliance has failed me.

TL:DR: US Airways made a false promise, and lost my bags