everyone else already said it, but yeah.. the molestation is probably the cause of all this uneasiness...
you were violated as a child, and you probably grew up feeling like sexual acts were dirty and wrong.
..it's really common for girls to feel like that if they were sexually abused... (or even if you
weren't abused-- just raised to believe that sexuality is taboo and "gross.")
personally, i feel a lot like you do.
i hate it when guys check out my boobs or my butt, (but that's because i'm completely uncomfortable with having any kind of curves).
but if i catch a guy just
looking at me (without
staring at my body), then it doesn't bother me. it's actually kind of flattering.
the only way that it would creep me out is if
the guy was creepy, or significantly older than me.
but, boys will be boys, and you just have to learn to ignore it.
(plus, i don't think that
every guy is undressing you with his eyes...
they probably just think that you're pretty, and you look like a sweet person who they'd like to be friends with.
)