Well, I used to look at myself and think I was massively fat,not helped by Twiggy, as I grew up in her hey day (hay day?). No one else thought I was.
I never seemed to have a lack of male interest - again, no one was finding 'fat' girls attractive, so I can't have been. Looking at photos, I can see I was a little bit plump when I was about 14. Again, looking at photos, I can see that puppy fat was gone very quickly, though I couldn't ever be bothered to diet as if I tried all I could think about was food, and food I didn't normally eat at tha, like chocolate bars and sweets. If I ate what I wanted it was mainly fruit and veg, I'd want an apple or banana in the same way others wanted choc.
So your own view of yourself is quite possibly inaccurate, very likely is. The main thing is to be satisfied with yourself as you are.
Best way I ever found to lose weight, apart from walking everywhere? Shagging.