i think your ethic should speak for itself... clearly you are not lazy...
if you feel it would help to discuss it with them then i would do it.. its usually pretty obvious when someone is trying to use something like this as an excuse... ie: they are just not trying and want a get out of jail free pass so to speak...
you're working hard and doing your best to get great grades... so how could they see it as an excuse..? when you hardly miss anything?

its not easy dealing with it alone... maybe they could help you a little even...