Breastfeeding

I definitely want to breastfeed and for as long as I can (my son will be here in May). So my question is... Is it gross to breastfeed your child till they are 2 or should I cut it off at a year old. I really want the bonding and even once I dry up and it just becomes dry nursing I want to. But thinking of the size of my son will be by 1-2 years I feel like people will look at me wrong like its gross. So who has breastfeed and for how long?