Hi Cathsp,
Your Son has done really well keeping clean.
The only thing I can suggest is to try and get your son some form of technology so he can join Zoom meetings on line, where he can talk to people who are going through the same thing and this would enable him to get a Sponsor and work through the 12 steps of Recovery.
There are lots of people on here with far more experience than I, so hopefully some other people might have some more suggestions.
I believe there is meetings for families of addicts too, you might find these useful.
Hope this helps, take care.
Dx