Yes, it is possible that there will be no mense while breastfeeding. It depends on individual body. For me, my mense returned when my no.1 is 2.5 years old and I am pregnant with no.3 without mense.
You will still ovulate while no mense and thus it is not a good method to prevent pregnancy if you are not planning for another baby yet.
http://kellymom.com/ages/older-infant/fertility/