to the groups jhawk!
I'm a calorie counter (fitday, My Fitness Pal, and caloriecount are good sites for writing down calorie intake). It depends on the day as to what I eat. Usually between 1300 and 1500 a day, sometimes as high as 1700, sometimes as low as 1100. I exercise 6 days a week (3 cardio days, 3 strength days). DH is overweight, but still eats what he wants.
If you're not feeling happy when you're eating healthy, then allow yourself a little treat (note that it's a "little" treat). My biggest pet peeve about dieting is people who say "you can't eat that!". Of course you can, but you have to decide if that's what you want. If you want a few chips with guacamole dip, then have them, just don't have the entire bag of chips; have 10; count them out. When you're finished with the 10, say to yourself "I'm finished". Denying yourself treats makes you want it all the more and denial will usually end up as a binge later. It's all about balance.
As for motivation, ask yourself WHY you want to lose weight. Is it to look dead sexy in underwear? Is it for your health? Are you losing weight to feel better about yourself or set yourself a challenge? Think about your reasons and your motivation will get stronger. Your reasons may even change over time; cool. When they change, you increase your motivation again.
Good luck with the diet.