This year it was the stadium opener against the Giants.
I hate that we lost to a clearly inferior team because they had the ball bounce their way a couple of times. It really bugged me that we opened the new stadium the wrong way much like we closed the old stadium the wrong way.
As for my worst loss ever it's a dead on tie between the Giants playoff game after the 2007 season and the final game at Texas Stadium last year.
Those two losses just killed me cause we should have won both of those games and just didn't get it done. Plus the meaning of those two games was big to me.
Almost everyone here keeps saying the 1994 NFC Championship game but I don't see that really. While it was very sad, and sucked that they lost, I was, and continue to be, extremely proud of that game because of how hard that team continued to fight back, continued to claw and scratch to have a shot to win the game.
Outside of the 3 Superbowl wins I've seen as a Cowboy fan I can't think of another game where I was as proud of a Cowboys team as I was that day.