You are a strong person stay that way! I was one of those that thought my son would turn his life around after getting into trouble because his sister did.
He did not!
Parents feel very guilty and go over and over in their minds, 'what did I (we) do to cause this and how can I (we) stop it'.
The addict is very manipulative and knows how to play on the hearts strings. In one sense your parents are correct, you are not the parent so you do not feel the guilt.
Sadly, you can not make them see what it is doing to them, and hopefully your brother will not go through their entire savings before they see him as an addict.
My son was in program after program and had so many chances. Now at 33 he was clean an sober for 1 year and going to college on the deans list.
He was in a bad relationship (they all are with him) and both relapsed (I didn't know she was recovering too) living with her mother. The girl kept harrassing us and I had to call the police to stop her. Turns out she (maybe both) were harrassing others.
I had started giving him money too because I did not want to accept that he was using again. THEN I STOPPED!!!
Now he is homeless, no job, no money, no friends, literally just the clothes on his back.
I hope he has bottomed out - your brother will have to too - and no one can save him but himself.
I am 59 and very tired of it - I wish I was as smart as you and had your strenght when I was your age.
