Never give up!
So many times you find yourself in losing chess games, difficult positions, down material, but let's face it...in how many of those games are you facing a GM or a computer that is flawless? Almost never right? In most cases, it is pretty likely they won't play the game perfectly from there on out, and just putting up a strong fight can many times demoralize them, tire them out, and they may end up losing or drawing the game. Here was a classic example of a case where the entire game was a big rollercoaster ride. I was up very early on, and then got too comfortable...ended up with a horrible position...and somehow managed to squeeze out a victory at the end.