welcome dvandjc
my heart goes out to you. last year i lost a friend, at age 50, just this way. he knew he was drinking himself to death, said he was aware of what he was doing and if anyone tried to stop him, he would cut them out of his life. the couple friends who tried to do an intervention on him met that fate. he died suddenly from heart complications.
i will PM you an article i read that you might be interested in.
i am sorry to hear of your cancer diagnosis. you have an awful lot on your plate right now. have you ever tried an al-anon meeting?
take care and keep coming back.