Surely it's not my overall poor diet choices...
Nobody ever gained weight from not eating.
/Has lost 130 pounds in the last year by simply not eating when I wasn't hungry, instead of eating when I'm bored or sad.
Supposedly "obese" is about 30% overweight. A lot of people are more than half of the way there. And it's probably due to the same factors that could get them to official obesity. Which often does _not_ include eating when bored. The biggest one may be directly related to aging.