According to dictionary.com a definition of listen is to wait attentively for a sound. Definition of hear is
to listen to; give or pay attention to. So yes I believe that these two actions are actually very different.
Someone can easily be listening to you and not hearing you. The action of listening implies that you are hearing the sounds of something. However it does not mean that you are hearing the words that someone is speaking to you. Also even when you are hearing someone it does mean that you are really hearing or understanding them.
Having conversations with people about things that you cannot understand because it simply does not make sense in your world makes it extremely hard to actually hear what they are saying.
Lesson learned- do my best to really listen AND hear them!!!