My husband & I are raising our granddaughter ~ her dad (my step-son, hubby's son) suffers from the disease of addition.
We have talked to our granddaughter about this because of his actions, her disappointments and all that goes with having an A father.
Most of all I have told her, it doesn't make him a bad person ~ it doesn't mean she shouldn't love him and it in NO way makes her a bad person because her dad has this problem.
I reassure her that WE still love him, but we just have to set limits and boundaries to keep our home a healthy place for her and for ourselves.
and I hold her very close when she cries and tell her it's ok to cry because this kind of stuff hurts and if Daddy was healthy, I'm sure he would never do anything to hurt her, but because he is not healthy right now, he can't make the best decisions.
and I hold her again.
Just my experience, strength and hope,
wishing you & your son the very best,