Be confident in who you are :)
Shes 100% right. There's not one person that doesn't go through this and if you say you haven't you're lying. For years and even now I have people look at me at certain times especially when I'm working out and ask me or someone close to me if I take steroids, or say I'm too big or whatever they wanna say to put me down. I've tried never let it get to me but usually it just motivates me to keep going and go harder.