Welcome jrose123, glad you're here. I'm sorry to hear you are in pain over your son's drinking.
Al-anon and individual therapy worked for me. I go to a meeting that is specifically for parents (though I am not one) and I wonder if there is some kind of support group near you like that, Al-Anon or not. There are people there with chilren who are in their 20s, 30s, 40s and 50s. Face to face support from people who understand is invaluable.
(Here is the link for your area, and they have several parents' groups:
http://www.ncwsa.org/district-14.html
If Al-Anon is not right for you, there might be something else. I highly recommend group support, as it worked for me. )
To answer your question, maybe you feel that way because it would be a way out of the pain. I think towards the end of AH and I living together I had that thought a time or two. I just felt it had all "won." Much like the addict drinks or drugs to numb their pain, I had my own unhealthy behaviors.
Are you able to get your grandson out of the house occasionally? It might help if he saw normal from time to time. The damage inflicted on the children in these situations breaks my heart.
Please keep posting - you're not alone in this and there are many people out there willing to help.
((()))