Joy---
I think Lizard gave you some wonderful advice. I can't imagine what you and your family may be going through. However, while you may not agree with his descion, believe it is "right" or support it; I would still support him in whatever way you could.Remember this is NOT about you nor is it your doing or reflect your parenting skills and what not. More importantly though, as a grandmother--- you mentioned he has 4 children; I think its important to remember that you are not only a mother, but a grand mother. Those precious children need you and if you choose dissaciate yourself from your son, you are also, in turn disassociating your self with you grand children-- which I am sure you do not want to do. Another thing I would strongly encourage--- and this goes along with the grand children, is although you may not agree with their father's life style choice, is to not let the grand children see the way you may feel. They are going to need as much positive support as possible. I know this is not exactly the same thing you are dealing with, but my parents got divorced after I was already an adult-- and the thing that bothered me the most, was when one parent said negative things about the other. No matter if I felt what the other parent was saying was true or not true, the fact that they got me involved made me feel pretty conflicted and "in the middle of them" per say.

Hang in there !