hi, lonely_guy.
I'm so sorry to hear about all that you have been through.
I would like to give you kudos, because, even though all of this has happened, you're doing a remarkably good job of keeping yourself together and taking care of your brother.
Like MsCarrie, I think this sounds like a grieving process. People try to fill the void with other things, like alcohol. It's a sad story sometimes, because these fillers can end up taking on a large part of one's life.. for a very long time.
Have you two been to counselling or any type of therapy? I think it would be good for the both of you, especially since he's having these thoughts of suicide.
If you ever have more thoughts racing through your head, never hesitate to Private Message me, or any other supporters on here. We're here to listen! I sincerely wish you the best!