no, it is not wrong of you to move on even though he needs help.
you are not the person to help him. think about it, has anything you've done helped him enter recovery? in fact, our "help" only enables the disease to progress further.
if you are sure that you "can't handle staying in the relationship" any longer, than why not communicate that immediately?
otherwise, your peace will continue to be disturbed and you will have this hanging over your head. it will minimize your stress to tell him right away.
i know it is the holidays but what about your holidays? he is with his parents, he will have their support as well as the support of his counselor. he's a grown up and you not wanting to be with him is the consequences of HIS choices.
naive