This is the most I've ever weighed

I got an office job full-time in December. The weight has been creeping on pretty steadily ever since. I'm one who has always been very conscious about my weight, and started MFP months ago just to keep track of my sugar intake mostly...but now that I'm suffering from sticker shock at my newest triple figure weight, I'm going to try harder to be more vigilant about tracking food and exercise. Ideally I'd like to lose 22 pounds...

Anyone else out there work at a desk job? How have you managed to keep off the weight while sitting all day?!?!

For exercise I'm a huge fan of walking and dance...I run in the summer when the weather is good but it kind of bores me so I don't stick with it for more than three months at a time...

Also, MFP suggests I keep my calories to about 1200... I always seem to eat around 1500 a day, even during past dieting attempts. I just can't seem to stick to 1200 without blowing it at the end of the day because of hunger. I know I'm supposed to exercise to allow for the deficit but with working so much I don't have time or energy for that every day. Suggestions welcome!

Thanks for reading and I look forward to getting inspiration by reading everyone's progress!