Mandalinn's 100% correct. You cannot control the scale, at all. Basing goals, especially time based ones, on things like the number on the scale is asking for failure. You absolutely must frame your goals in doable, positive terms. Instead of weighing _______ by X date, why not say "I will eat between 1600-1800 calories every day, without overages, for the next two months" and then weigh yourself at the end and celebrate your inevitable losses? You didn't fall two or three pounds short of your goal, you succeeded at getting five pounds off!
Negative self talk will destroy you faster than any happy meal. In this, you are in control. Speak kindly to yourself, live out actions that have positive connotations and results, and always celebrate the glass half full, not the little bit that spilled. And that goes for life in general, not just weight loss.
Now, granted, even obese I was one of those unbearably cheerful people, but I have also loved myself at every weight I've been at, and every slow pound gone has been a victory. I highly suggest you try a positive outlook and positive goals, I think the benefits will surprise you