You have a reunion coming up. There is a friend's wedding in the near future. Your family's beach vacation is around the corner. Your intention is to "lose a few." Time passes. You go to visit your family. They say "You look great." Relief. Worse: They don't say anything. Shame... you should have worked harder on this.
We "weight." We have learned to associate the upcoming events, celebrations and vacations with a need to improve our bodies. We expect (maybe because of past experiences) that acceptance from others is conditional, and that our bodies mean something about who we are.