Living with an alcoholic spouse?

I met my husband when we were 28 and 29. Had been out of a long 5 year relationship for 3 years with a 3 year old child. Met a very kind, sensitive man who fell in love with me and loved my child, We dated for less that 5 months and got married. We were very excited about making us a family so shortly after we were married my husband applied to adopt my son. Within a year after our marriage I became pregnant, we bought a house and had our second child. When I met my husband, I knew he liked to drink and many times we would go with friends and I enjoyed it too but not to excess. As the kids grew older his drinking became worse over time. In 1997 our first son committed suicide after several ears of gliding into the wrong track with drugs, alcohol and wrong friends, This started the slide of m husband really headed down the constant drinking path. I cried a lot he drank more. Over the past 15 years it has been a constant road of destruction for him. In and out of rehab. Many, many medical issues. He has completely alienated himself from all friends, family and worst of all his own son and myself. 1 and ½ year ago he left home in a fit of drunk anger and headed to Florida as we have a trailer down there for the winter. He has had a near death experience a year ago at which he was so far gone that he was in hosp. for 6 weeks and I was told mentally his brain was so deteriated that he would have to spend the rest of his life in a nursing home. Miraculously he did not stay in this state of mind and went into rehab again at the VA. He seemed to be doing well for some time but now is back in the same situation, still claims I am the love of his life after 38 years but has given up on life , feels he no longer even wants to try and it will probably only be a matter of time. As much as this has hurt me more than I can even explain, it is so very hard to tell him I can no longer live this life because it is destroying me, There are times I feel very angry at him because when you have a good life and a family that has tried so hard to help you get better, why are you still resisting. On other days I feel so helpless but also feel manipulation on his part jut to keep me hanging on. I don’t know what is the truth any more.
What does one do in a situation like this?