I was definitely in the same boat as you, for some reason the first time I measured myself was more of a slap in the face than seeing I had passed 300lbs! It sucks now, but man you be so glad you did it later on! This way, if you stop seeing the scale go down, you can track your measurements instead and not get discouraged. It's really helped me so far, and I can't wait to measure myself when I'm at my goal weight, the numbers will be fun to compare.
