Unfortunately, alcoholism is a disease that makes EVERYONE involved with the alcoholic sick. You start to doubt yourself because you live with a person who says one thing, then does another. They aren't consistent in their actions or their words. After awhile you start to get frustrated, then you want them to stop drinking, then you try to make them stop drinking, and then you get kinda crazy yourself because they keep saying they'll quit yet they continue to drink.
Pick up "Codependent No More" by Melodie Beattie. If you can, attend an Al-Anon meeting - give it a try. The meetings will NOT tell you how to get the alcoholic sober, but they will help you to realize you're dealing with someone who has a disease. You will learn more about yourself. You will also learn there is nothing you can do to get an alcoholic sober. They have to do that on their own.
The 3 C's: you didn't cause it, you can't control it, and you can't cure it. I'm sure you love your husband very much, but you have no power to make him quit drinking. Don't take it personally when he says things that make you think he wants you to leave. A lot of alcoholics isolate themselves and want everybody, including their spouse and children, to just leave them alone. I've lived alone with my husband for quite awhile. Sometimes he comes back and connects and is wonderful, but far too often he just zones out and acts as if I'm not here. That's the nature of the disease, and it's a tragedy.