Chickory, you dont have to get any smarter and you are doing your best, today, right now. I really, know how you are feeling right now, it is horrible.
When I realized that my feelings were hurt because my son wasnt living the life I expected and he wasnt treating me the way that I expected - this is when I knew it was out of my control.
I could only put up with so much from a person I didnt even know. It was the only way I could detach (from my son and the monster). Maybe try thinking visualizing your son as a person you dont even know, it will be easier to say NO thanks, I wont except this anymore. I had to separate my emotions and the fact I had given birth to this monster. I had to be patient and have the 'faith' to hope that my son would come back some day. Very painful, very frightening but I had to believe that the son I knew, had the strength to pull himself up without my hands. Your son can do it, if he really wants it. He will respect you for giving him that strength as he becomes the man who builds his own future.
JJ