I want to step in and say don't let it depress you.
I'm sure a lot of people loved who you were in High School. While you don't, they do remember you that way. And not necessarily with criticism.
Everyone who sees that photo will admire your hard work and life experience.
YOU should respect your own hard work and achievement.
That young large girl was probably going through a lot of things and people would probably be so glad for her, that she was able to balance her life and recover. Most people, especially from high school on, just get older, fatter and unhappier. We're all trying not to head down that route