It is a horrible situation, but you are not a horrible person. I think many have had similar thoughts. Like others have shared, I used to daydream of the funeral. Not so much the death, but just a funeral. I felt trapped, and sometimes death (his not mine) felt like the only way I'd ever be free. The only way to get out, to breath.
What we have discovered, or are in the process of discovering here, is that we are not forever shackled to the emotional pain and suffocation of loving an alcoholic. We don't need death to save the day. We can save ourselves.
Perhaps you can begin to look for ways to emotionally free yourself from some of the trauma. Al-Anon may have a map. Have you tried al-anon? I've heard there are groups for adult children of alcoholics but I've never been to one.
You, and your brother, are in my thoughts today. I do acknowledge the incredibly difficult hand you've been dealt. You are not bad, or weird, or crazy for your expressions of pain. They are normal. Do not feel guilty. I wish for you both the healing of your hearts and souls.