Breastfeeding creeps me out, why???

I don't understand why. I'm currently pregnant and plan to breastfeed but only for about four months. Once my baby can grab at my boob, I will stop. I hate that it creeps me out being it's natural... I think what's most creepy is when a momma is doing it to a 6month-older baby boy. Could this have anything to do with being sexually assaulted before??? Please give me some good feedback on reasons why it shouldn't creep me out.