So close, yet so far away

After noticing for the past week that all of my clothes were getting loose I decided yesterday to go try on clothes at Rochester Big & Tall. A year ago when I weighed 417 I was pushing 5XL, although I never bought anything at that size (I would just squeeze into the 4XL, popping a few buttons along the way). Also, my waist size was 52. But I'm glad to report that now I'm fitting comfortably into 3XL and was able to slide into Ralph Lauren jeans with a 46 waist. They were a bit snug, but it boosted my confidence as well as my committment to this weight-loss regime I'm on.

That said, when I think about my goal of reaching 220 pounds it still seems so far away. I've lost about 40, but how long will it take to lose another 150? Will I be able to do it? I'm taking it one day at a time, but I'm setting some short-term goals that I hope to achieve while making it toward the big one. If I can lose five pounds a week until I reach 310 and then three pounds a week after that, here's what I'm working toward achieving:

By March 1: 350
By April 1: 330
By May 1: 310
By June 1: 295
By July 1: 280
By August 1: 265
By September 1: 250
By October 1: 235
By November 1: 220

At this rate I'll reach my goal by Thanksgiving. This sounds impossible, and I promise not to beat myself emotionally if I don't achieve this. But I really do believe I can do it if I continue the path I'm on and steadily ramp up the exercise along the way. What do you think? Can I do it?