Kind of linked to what Lingula said about having fun is your own mental state. I played in a local tournament a couple of months back with a Poe, Corran, A-Wing list. First game out I lost Poe for no enemy loss in a flurry of appalling dice, I *almost* decided I'd lost that game straight away. I took a few seconds, told myself to man up and let Corran and his wingman do their thing, and concentrated on making the best of a bad situation. I ended up winning that game, and all the others save the final game against the eventual tournament champ. I've seen a lot of players hold their hands up in despair at the slightest set back, and you simply can't play your best when you're in that frame of mind. Stay positive, stay focused and put your trust in the Force.
As a by-product it makes you a much nicer person to play games against too!