I know what it’s like being very skinny and getting your health questioned all the time. I also found when I was underweight that people had no shame in commenting on my body. Like when it’s the opposite, and someone is over weight people are sensitive about it because they understand weight is a touchy subject, but when someone is too skinny people Somehow think it’s okay to comment on it? I’ve heard countless comments and skeleton jokes and some of them were quite mean and really hurt me. don’t know if you can relate.
I just wanted to point out that metabolism slows down with age for all of us, so even you WILL gain weight more easily sooner or later and while it has its downsides i still think it’s better being on that side rather than the slow side..! And same with looking young, you might not find it so bad when in your 50s? =)
Also it’s really hard to have a “childish” looking body with a D-cup, I think much of it might be your old self image messing with you!