Your post brought me to instant tears
I can so relate to you with the caregiving part ,and the loving you have in your heart for him. Also the wish of him not having to suffer anymore and being able to go peacefully
I'ts hard to not feel selfish either way. Knowing that they will have to no longer endure their physical pain once they pass on but at the same time not wanting them to leave you. The thought of not having your loved one to be with every day is very hard. My 1st husband also had alcoholism and while things didn't work out for us, i know a lot of the things you have had to go thru. You are a very strong woman to stay and i imagine your love for your husband held you to your marriage. He is a very lucky man to have you and i'm sure he knows this by you saying he tells you all the time that he loves you.
Sometimes in life having another person to talk to means the world and can be a great stress reliever. So never feel you have to apologize for your anger.........it's a natural human emotion to have when you don't want the man of your life to ever leave you
Enjoy your days the two of you have left because they are so very special. When you feel the anger at him start to build up think of all your many good times. Take out photo albums, videos if you have any of years past ? Share the good past moments with your husband also when able. Give him peace of mind that you always love him no matter what. That he's the best thing that could have ever happened to your life........love him deeply and forever