Welcome to SR
I think Ann said everything I was going to.
The addict (who I also love dearly ) is my 20 yr old daughter.
Tough Love has been a challenge for me. I kept falling for my daughter's guilt trips, but now I am better and have my guard up.
Our addicts seem to catch us off guard and we sometimes go back to the enabling ways of the past. It seems that your son-in-law is on the right track as far as the tough love.
What we say here at SR is do what you feel is right for you to do. I certainly didn't manage to get the tough love attitude over night. I had to take baby steps in order to finally "get it".
Good luck and keep posting here. This site has literally saved my life. We all value from each others' experiences.
Hugs to you
Terri