I am so sorry you are in such a state of hopelessness in regards to your brother. I know how strong of a connection I have to my brother. Mine is still young and presumably on a good path so that puts me at ease but I can empathize with you and how it must feel to seemingly be losing someone so close.
There are groups that have been proven to be very helpful to a lot of people in your situation. I strongly believe the framework and proven track record of AA and also Alanon (which is the family/loved ones version of AA) are so helpful. Basically Alanon followers go through the same 12 steps that AA follows but it focuses on the fact that instead of you being helpless to your addiction as an alcoholic or drug user, you are helpless to your using loved one. It helps you learn how to cope with your hopelessness and complete and utter lack of control in regards to your brothers problems. It helps you learn that yes it is sad that you have no say in what he does but you do have a say in what you allow to affect you. It helps you let go but in a sane and methodical manner with a support group of people going through your same pain. It guides you and gives you a support and structure.
Alanon and AA are not just for alcoholics, although it may seem as though at first because of the name. The miraculous part of AA and Alanon is that the 12 steps are not specific to alcohol and they can be used in any addictive situation from alcohol, drugs, sex, gambling, anything that causes an imbalance for that manner.
I know a lot of people are steered away from it right off the bat because it is intimidating. There are strict guidelines and mannerisms to to programs that make new comers not understand. A lot of times during your first meeting, in your haze of anguish and desperation you attend a meeting like this hoping for the ultimate answer. There are no answers as to why your loved one does what he does. It just happens. The program doesn't even allow that question to be exercised because it just distracts you from the healing process as you sit and try and justify "why" in your head. This is why the program can confuse and scare off a newcomer. When you bring up the "why" aspect you will get a lot of text book answers like "you cannot control an addiction." It's basically getting all of the answers you didn't want to hear by going there. What you have to understand is that these people are far into the program and they have begun to accept they have no control and dwelling on the abuser and allowing them to affect their life is pointless and unhealthy.
The program is hard to accept because it isn't comforting in the traditional manner. You have to go through a process of acceptance which is not what you want to do. You don't want to accept your loved one is in control of their own destiny and that you cannot affect their decisions. But it really does help you, and you WILL one day be able to live a life without worrying about him. Because as much as you love him, worrying about him is just hurting you. What is going to happen will happen whether you worry or not. So you might as well learn to live without it.
I hope this was helpful to you.


