I too am the mother of an addict (only child/foster child) and my heart and prayers go out for you and your family.
You are wise to think of his well-being, he needs your love and support and perhaps some family counseling would be helpful, as well as counseling for him. As Laurie suggested, I would seek out a counselor that specializes in addiction and how it affects the family.
I'm glad you found us and hope you find peace and support here.
Hugs