I feel like the same thing has been happening to me for the last several years. I feel the same as I always have, though I'm heavier now than I ever have been before. I don't notice when I gain 10 lbs because my clothes are all fairly baggy, or they get tight and I get the next size without thinking about it.
This is me, right after Christmas '08:
I probably weigh 10 lbs more now than when that photo was taken. Maybe more. Lately when I look in the mirror (although it's unusual for me to see myself in a mirror that goes below my shoulders), I notice new things about myself, like how I don't look thin from any angle anymore, and how when I strike a model pose I can see a little bit of cellulite on my arms. When did that happen?
I wish I could just "snap out of it" and dramatically become a thin, successful, socially-adept, mentally healthy person. I think I'm starting to get that it's not going to happen like that. It's small changes, a little at a time, or it's a no-go.
Here's a quote I found on sparkpeople.com. I'm trying to find more "small step at a time" kind of quotes, but this is the only one I have so far:
"Be not afraid of going slowly; be afraid only of standing still." - Chinese Proverb