This usually occurs between ages six to nine months. Try going into a quiet, dark room to breastfeed. Your baby may start waking more at night to feed, when nothing interesting is going on. You may not like having your sleep disturbed, but at least your baby is getting the perfect nourishment his body requires. This is less of a problem if your baby sleeps in your bed.
Night waking is also common during teething, anyway.
A baby will often pick up on breastfeeding during the day at about one year, when he starts standing, walking and falling down and hurting himself a lot. Perhaps you have a very busy baby who sucks his thumb, has always preferred sleeping alone, has adopted a blankie or teddy bear. We call these babies self-soothers. It's less common among breastfeeding babies, but they do exist. Perhaps you are pregnant, and your baby is reacting to the change in the taste or quantity of your milk.